Ascendis Pharma A/S (ASND)

INCORPORATION BY REFERENCE This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336 and 333-282196) of Ascendis Pharma A/S (the “Company”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished. Warrant Grants On September 8, 2026, the Company’s board of directors granted an aggregate of 29,380 warrants to certain employees of the Company (the “Warrants”) under the terms of Appendix 1a to the Company’s Articles of Association. […]

SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Ascendis Pharma A/S Date: September 9, 2026 By: /s/ Michael Wolff Jensen Michael Wolff Jensen Executive Vice President, Chief Legal Officer

This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336 and 333-282196) of Ascendis Pharma A/S (the “Company” or “Ascendis”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished.

On August 31, 2026, the Company announced that it has entered into a binding term sheet for a global settlement and license agreement with BioMarin Pharmaceutical Inc. (“BioMarin”) related to the sale of YUVIWEL ® and navepegritide-related products. The binding term sheet provides the terms and conditions upon which the companies agree to resolve all litigation and disputes between the companies. Under the terms, BioMarin has agreed to grant Ascendis a non-exclusive, worldwide, royalty-bearing license, allowing Ascendis to continue researching, developing, manufacturing, and commercializing navepegritide-related products without restriction. Furthermore, BioMarin has agreed to waive certain regulatory rights and exclusivities, dismiss all proceedings, and provide a covenant not to sue relating to the covered intellectual property. […]

This report contains forward-looking statements that involve substantial risks and uncertainties. All statements, other than statements of historical facts, included in this report regarding Ascendis’ future operations, plans and objectives of management are forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. Examples of such statements include, but are not limited to, statements relating to (i) the resolution of litigation and disputes between Ascendis and BioMarin pursuant to the binding term sheet and anticipated definitive agreement, and (ii) the continued research, development, manufacturing and commercialization of navepegritide-related products. […]

technology disruptions; and the impact of international economic, political, legal, compliance, public health, and business factors, including tariffs, trade policies, currency fluctuations, and geopolitical events. For a further description of the risks and uncertainties that could cause actual results to differ from those expressed in these forward-looking statements, as well as risks relating to Ascendis’ business in general, see Ascendis’ Annual Report on Form 20-F filed with the U.S. Securities and Exchange Commission (SEC) on February 11, 2026, and Ascendis’ other future reports filed with, or submitted to, the SEC. Forward-looking statements do not reflect the potential impact of any future licensing, collaborations, acquisitions, mergers, dispositions, joint ventures, or investments that Ascendis may enter into or make. Ascendis does not assume any obligation to update any forward-looking statements, except as required by law.

SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Ascendis Pharma A/S Date: August 31, 2026 By: /s/ Michael Wolff Jensen Michael Wolff Jensen Executive Vice President, Chief Legal Officer

Furnished as Exhibit 99.1 to this Report on Form 6-K is a press release of Ascendis Pharma A/S (the “Company”) dated August 13, 2026, announcing the Company’s financial results for the fiscal quarter ended June 30, 2026. Exhibits Exhibit No. Description 99.1 Press Release dated August 13, 2026.

SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Ascendis Pharma A/S Date: August 13, 2026 By: /s/ Michael Wolff Jensen Michael Wolff Jensen Executive Vice President, Chief Legal Officer

INCORPORATION BY REFERENCE This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336 and 333-282196) of Ascendis Pharma A/S (the “Company” or “Ascendis”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished. Information Contained in this Report on Form 6-K Financial Statements This report contains the Company’s Unaudited Condensed Consolidated Interim Financial Statements as of and for the period ended June 30, 2026, including Management’s Discussion and Analysis of Financial Condition and Results of Operations for the period […]

SIGNATURE Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Ascendis Pharma A/S Date: August 13, 2026 By: /s/ Michael Wolff Jensen Michael Wolff Jensen Executive Vice President, Chief Legal Officer

1. Unaudited Condensed Consolidated Interim Financial Statements – June 30, 2026 F- 1 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations 1

ASCENDIS PHARMA A/S INDEX TO UNAUDITED CONDENSED CONSOLIDATED INTERIM FINANCIAL STATEMENTS Page Unaudited Condensed Consolidated Interim Statements of Profit or (Loss) and Other Comprehensive Income or (Loss) for the Three and Six Months Ended June 30, 2026 and 2025 F-2 Unaudited Condensed Consolidated Interim Statements of Financial Position as of June 30, 2026 and December 31, 2025 F-3 Unaudited Condensed Consolidated Interim Statements of Changes in Equity for the Six Months Ended June 30, 2026 and 2025 F-4 Unaudited Condensed Consolidated Interim Statements of Cash Flows for the Six Months Ended June 30, 2026 and 2025 F-5 Notes to the Unaudited Condensed Consolidated Interim Financial Statements F-6

Unaudited Conden sed Consolidated Interim Statements of Profit or (Loss) and Other Comprehensive Income or (Loss) for the Three and Six Months Ended June 30, 2026 and 2025 Three Months Ended June 30, Six Months Ended June 30, (EUR’000, except per share data) Notes 2026 2025 2026 2025 Consolidated Statement of Profit or (Loss) Revenue 5 339,285 158,045 585,886 258,998 Cost of sales ( 27,658 ) ( 31,447 ) ( 45,173 ) ( 48,963 ) Gross profit 311,627 126,598 540,713 210,035 Research and development expenses ( 75,888 ) ( 71,988 ) ( 134,932 ) ( 158,591 ) Selling, general, and administrative expenses ( 173,341 ) ( 107,561 ) ( 318,571 ) ( 208,608 ) Other operating income 4 158,067 — 158,067 — Operating profit/(loss) 220,465 ( 52,951 ) 245,277 ( 157,164 ) Share of profit/(loss) of associates 3,836 ( 4,097 […]

INCORPORATION BY REFERENCE This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336 and 333-282196) of Ascendis Pharma A/S (the “Company”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished. Warrant Grants On August 11, 2026, the Company’s board of directors granted an aggregate of 15,060 warrants to certain employees of the Company (the “Warrants”) under the terms of Appendix 1a to the Company’s Articles of Association. […]

SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Ascendis Pharma A/S Date: August 12, 2026 By: /s/ Michael Wolff Jensen Michael Wolff Jensen Executive Vice President, Chief Legal Officer

This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336 and 333-282196) of Ascendis Pharma A/S (the “Company” or “Ascendis”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished.

Treatment with the combination of once-weekly TransCon CNP and once-weekly TransCon hGH continued to demonstrate durable growth in children with achondroplasia, with a mean annualized growth velocity (AGV) meeting or exceeding the 97 th percentile of children of average stature, without compromising safety or tolerability at Week 78.

Consistent with Week 26 and Week 52 results, mean AGV for children treated with combination therapy through Week 78 remained at or above the 97 th percentile AGV of children of average stature, with changes over time following age-related growth patterns, and sustained increases in ACH-specific height Z-score, indicating a tripling of efficacy compared to TransCon CNP monotherapy.

For the TransCon CNP treatment-naïve cohort, mean AGV at Week 78 was 7.73 cm/year, with an increase in mean ACH-specific height Z-score of +1.29, increasing from 0.46 to 1.75 over 78 weeks.

For the TransCon CNP-experienced cohort (mean treatment duration with TransCon CNP of 2.56 years), mean AGV at Week 78 was 7.67 cm/year, with an improvement in mean ACH-specific height Z-score of +1.10, increasing from 1.28 to 2.38 over 78 weeks.

INCORPORATION BY REFERENCE This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336 and 333-282196) of Ascendis Pharma A/S (the “Company”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished.

On July 14, 2026, the Company’s board of directors granted an aggregate of 14,060 warrants to certain employees of the Company (the “Warrants”) under the terms of Appendix 1a to the Company’s Articles of Association. In connection with the grant of these Warrants, the Company amended its Articles of Association to provide for the grant of these Warrants. Each Warrant confers the right to subscribe for one ordinary share of the Company and has an exercise price equal to US $265.57 per share, the closing price of the Company’s ordinary shares as reported on the date of grant. […]

After giving effect to the grant of the Warrants described above, warrants to subscribe for an additional 1,539,503 shares of the Company remain available for future grant by the Company’s board of directors pursuant to the Company’s Articles of Association. The foregoing description of the material terms of the Warrants is qualified in its entirety by reference to the Company’s Articles of Association, which is included as Exhibit 1.1 hereto and incorporated by reference herein.

SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Ascendis Pharma A/S Date: July 15, 2026 By: /s/ Michael Wolff Jensen Michael Wolff Jensen Executive Vice President, Chief Legal Officer

This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336 and 333-282196) of Ascendis Pharma A/S (the “Company” or “Ascendis”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished.

On June 30, 2026, the Company announced new radiographic data from Week 104 from the completed pivotal ApproaCH Trial of once-weekly TransCon CNP (navepegritide) in children with achondroplasia. In the trial, TransCon CNP-treated children demonstrated continued improvements in lower extremity alignment through up to two years of treatment, including improvements in tibial-femoral angle (TFA). As previously reported, improvements in annualized growth velocity were maintained and ACH-specific height Z-score increased with TransCon CNP treatment through Week 104. The data were presented by Leanne M. Ward, M.D., FRCPC, Professor of Pediatrics at the University of Ottawa and Children’s Hospital of Eastern Ontario, during the 12th International Conference on Children’s Bone Health (ICCBH 2026) held in Montreal, Canada.

ApproaCH was a randomized, double-blind, placebo-controlled pivotal trial in 84 children with achondroplasia aged 2–11 years, investigating TransCon CNP (100 µg/kg once-weekly) versus placebo for 52 weeks, followed by an open-label extension (OLE) in which all participants received TransCon CNP through Week 104. Radiographic assessments of lower extremity alignment were conducted at baseline, Week 52, and Week 104.

Improvements in TFA and TFA Z-scores continued through Week 104 and were greater in children with baseline TFA ≥ 5°:

The average TFA in all children treated with TransCon CNP during the double-blind period was 9.1° at baseline, decreasing to 7.7° at Week 52 and 6.9° at Week 104, reflecting a mean absolute change of -2.2 degrees over the two-year treatment period. In the subgroup of children with baseline TFA ≥ 5° (reflecting children with preexisting genu varum), the average TFA was 13.4° at baseline, decreasing to 11.3° at Week 52 and 9.6° at Week 104, reflecting a mean absolute change of -3.8 degrees over the two-year treatment period.

INCORPORATION BY REFERENCE This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336 and 333-282196) of Ascendis Pharma A/S (the “Company” or “Ascendis”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished.

On June 29, 2026, an exercise window closed for the Company’s outstanding warrants exercisable for the Company’s ordinary shares, nominal value DKK 1. In connection with the exercises of certain of such warrants during this exercise window, the Company registered aggregate share capital increases of nominal DKK 177,267 with the Danish Business Authority, corresponding to an aggregate increase in the Company’s share capital to nominal DKK 66,189,926 through the issuance of 177,267 ordinary shares against average cash consideration of approximately USD $121.57 per share, based on the DKK-USD exchange rate on June 29, 2026. The Company’s articles of association were amended accordingly and are attached hereto as Exhibit 1.1.

SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Ascendis Pharma A/S Date: June 29, 2026 By: /s/ Michael Wolff Jensen Michael Wolff Jensen Executive Vice President, Chief Legal Officer

INCORPORATION BY REFERENCE This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336 and 333-282196) of Ascendis Pharma A/S (the “Company” or “Ascendis”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished. On June 17, 2026, the Company completed the previously announced sale of its Rare Pediatric Disease Priority Review Voucher (the “PRV”) to an undisclosed buyer for $187.5 million in cash, before transaction-related expenses. The PRV was awarded by the U.S. […]

SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Ascendis Pharma A/S Date: June 17, 2026 By: /s/ Michael Wolff Jensen Michael Wolff Jensen Executive Vice President, Chief Legal Officer

This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336 and 333-282196) of Ascendis Pharma A/S (the “Company” or “Ascendis”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished.

On June 13, 2026, the Company announced Week 182 data from its completed Phase 3 PaTHway Trial showing that long-term treatment with TransCon PTH (palopegteriparatide) demonstrated sustained efficacy and safety in adults with hypoparathyroidism. Over the three-and-a-half-year duration of the trial, TransCon PTH replicated the systemic actions of endogenous PTH, with a balanced, beneficial impact on the main target organ systems – CNS, kidney, small intestine, and bone – as demonstrated by improved quality of life and normalized and stable urine calcium, serum calcium, serum phosphate, and bone mineral density. These benefits were sustained while enabling independence from conventional therapy with active vitamin D and calcium.

86% of patients were responders for the multi-component endpoint of (1) serum calcium in the normal range, (2) taking no active vitamin D, and (3) taking ≤600 mg/day of calcium.

100% of patients achieved independence from active vitamin D, defined as not taking calcitriol or alfacalcidol.

96% of patients achieved independence from therapeutic doses of calcium, defined as taking < 600 mg/day of calcium.

INCORPORATION BY REFERENCE This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336 and 333-282196) of Ascendis Pharma A/S (the “Company” or “Ascendis”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished. On June 11, 2026, the Company announced 5-year (Week 266) data from its Phase 2 PaTH Forward Trial showing that long-term treatment with TransCon PTH (palopegteriparatide) demonstrated sustained efficacy and safety in adults with hypoparathyroidism. […]

enrolled (95%) completed the five-year trial. Endpoints included independence from conventional therapy (defined as <600 mg/day of calcium and no active vitamin D) and maintenance of normocalcemia (8.3 to 10.6 mg/dL). Renal function was assessed by estimated glomerular filtration rate (eGFR). Bone mineral density (BMD) measured by DXA scan was assessed at baseline and regular intervals through Week 266. Hypoparathyroidism-related symptoms and functional impacts were measured using the HPES. Health-related quality of life was measured using the 36-Item Short Form Survey (SF-36 version 2). Safety assessments included treatment-emergent AEs and 24-hour urine calcium excretion.

SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Ascendis Pharma A/S Date: June 12, 2026 By: /s/ Michael Wolff Jensen Michael Wolff Jensen Executive Vice President, Chief Legal Officer

INCORPORATION BY REFERENCE This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336 and 333-282196) of Ascendis Pharma A/S (the “Company”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished. Warrant Grants On June 9, 2026, the Company’s board of directors granted an aggregate of 27,030 warrants to certain employees of the Company (the “Warrants”) under the terms of Appendix 1a to the Company’s Articles of Association. […]

SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Ascendis Pharma A/S Date: June 10, 2026 By: /s/ Michael Wolff Jensen Michael Wolff Jensen Executive Vice President, Chief Legal Officer

INCORPORATION BY REFERENCE This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336 and 333-282196) of Ascendis Pharma A/S (the “Company”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished. Warrant Grants On May 12, 2026, the Company’s board of directors granted an aggregate of 31,250 warrants to certain employees of the Company (the “Warrants”) under the terms of Appendix 1a to the Company’s Articles of Association. […]

SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Ascendis Pharma A/S Date: May 13, 2026 By: /s/ Michael Wolff Jensen Michael Wolff Jensen Executive Vice President, Chief Legal Officer

Furnished as Exhibit 99.1 to this Report on Form 6-K is a press release of Ascendis Pharma A/S (the “Company”) dated May 7, 2026, announcing the Company’s financial results for the fiscal quarter ended March 31, 2026. Exhibits Exhibit No. Description 99.1 Press Release dated May 7, 2026.

SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Ascendis Pharma A/S Date: May 7, 2026 By: /s/ Michael Wolff Jensen Michael Wolff Jensen Executive Vice President, Chief Legal Officer

INCORPORATION BY REFERENCE This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336 and 333-282196) of Ascendis Pharma A/S (the “Company” or “Ascendis”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished. Information Contained in this Report on Form 6-K Financial Statements This report contains the Company’s Unaudited Condensed Consolidated Interim Financial Statements as of and for the period ended March 31, 2026, including Management’s Discussion and Analysis of Financial Condition and Results of Operations for the period […]

SIGNATURE Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Ascendis Pharma A/S Date: May 7, 2026 By: /s/ Michael Wolff Jensen Michael Wolff Jensen Executive Vice President, Chief Legal Officer

1. Unaudited Condensed Consolidated Interim Financial Statements – March 31, 2026 F- 1 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations 1

ASCENDIS PHARMA A/S INDEX TO UNAUDITED CONDENSED CONSOLIDATED INTERIM FINANCIAL STATEMENTS Page Unaudited Condensed Consolidated Interim Statements of Profit or (Loss) and Other Comprehensive Income or (Loss) for the Three Months Ended March 31, 2026 and 2025 F-2 Unaudited Condensed Consolidated Interim Statements of Financial Position as of March 31, 2026 and December 31, 2025 F-3 Unaudited Condensed Consolidated Interim Statements of Changes in Equity for the Three Months Ended March 31, 2026 and 2025 F-4 Unaudited Condensed Consolidated Interim Statements of Cash Flows for the Three Months Ended March 31, 2026 and 2025 F-5 Notes to the Unaudited Condensed Consolidated Interim Financial Statements F-6

Unaudited Conden sed Consolidated Interim Statements of Profit or (Loss) and Other Comprehensive Income or (Loss) for the Three Months Ended March 31, 2026 and 2025 Three Months Ended March 31, (EUR’000, except per share data) Notes 2026 2025 Consolidated Statement of Profit or (Loss) Revenue 5 246,601 100,954 Cost of sales ( 17,515 ) ( 17,517 ) Gross profit 229,086 83,437 Research and development expenses ( 59,044 ) ( 86,603 ) Selling, general, and administrative expenses ( 145,230 ) ( 101,046 ) Operating profit/(loss) 24,812 ( 104,212 ) Share of profit/(loss) of associates ( 10,251 ) 26,579 Finance income 4,517 28,854 Finance expenses ( 67,255 ) ( 44,786 ) Profit/(loss) before tax ( 48,177 ) ( 93,565 ) Income taxes (expenses) 4 677,516 ( 1,061 ) Net profit/(loss) for the period 629,339 ( 94,626 ) Attributable to owners of […]

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): ☐

INCORPORATION BY REFERENCE This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336 and 333-282196) of Ascendis Pharma A/S (the “Company” or “Ascendis”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished. Redemption of Convertible Notes The Company has called all $575.0 million aggregate principal amount of its outstanding 2.25% Convertible Senior Notes due 2028 (the “notes”) (CUSIP No. 04351P AD3 / ISIN No. US04351PAD33) for redemption on May 6, 2026 (the “Redemption Date”). […]

U.S. Bank Trust Company, National Association, is acting as Trustee, paying agent and conversion agent under the Indenture, and its address (which is a place of payment under the Indenture) is 111 Fillmore Avenue E, Saint Paul, MN 55107, Attention: Corporate Action – Specialized Finance. This report does not constitute a notice of redemption with respect to the notes. The notice of redemption is being delivered to holders separately in accordance with the terms of the Indenture. This report is neither an offer to sell nor a solicitation of an offer to buy the notes or any other securities and shall not constitute an offer to sell or a solicitation of an offer to buy, or a sale of, the notes or any other securities in any jurisdiction in which such offer, solicitation or sale is unlawful. […]

SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized. Ascendis Pharma A/S Date: April 21, 2026 By: /s/ Michael Wolff Jensen Michael Wolff Jensen Executive Vice President, Chief Legal Officer

INCORPORATION BY REFERENCE This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336 and 333-282196) of Ascendis Pharma A/S (the “Company”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished.

In connection with announcements relating to the Company’s listing of its ordinary shares directly on The Nasdaq Global Select Market, the Company previously disclosed the International Securities Identification Number (“ISIN”) for the Company’s ordinary shares as DK0060606333. However, the applicable ISIN following the listing is now DK0060615755, as confirmed by the National Numbering Agency for Denmark. The CUSIP number (K08588103) and the ticker symbol (ASND) for the Company’s ordinary shares previously reported by the Company remain unchanged.

SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized. Ascendis Pharma A/S Date: April 21, 2026 By: /s/ Michael Wolff Jensen Michael Wolff Jensen Executive Vice President, Chief Legal Officer

INCORPORATION BY REFERENCE This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336 and 333-282196) of Ascendis Pharma A/S (the “Company”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished. On April 20, 2026, the Company announced the commencement of trading of its ordinary shares on The Nasdaq Global Select Market (“Nasdaq”), replacing the listing of American Depositary Shares (“ADSs”). The ordinary shares trade under the same ticker symbol “ASND” as previously used for the ADS listing. […]

SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Ascendis Pharma A/S Date: April 20, 2026 By: /s/ Michael Wolff Jensen Michael Wolff Jensen Executive Vice President, Chief Legal Officer

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): ☐

INCORPORATION BY REFERENCE This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336 and 333-282196) of Ascendis Pharma A/S (the “Company”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished.

On April 14, 2026, the Company’s board of directors granted an aggregate of 32,310 warrants to certain employees of the Company (the “Warrants”) under the terms of Appendix 1a to the Company’s Articles of Association. In connection with the grant of these Warrants, the Company amended its Articles of Association to provide for the grant of these Warrants. Each Warrant confers the right to subscribe for one ordinary share of the Company and has an exercise price equal to US $249.84 per share, the closing price of the American Depositary Shares (“ADS”) representing the Company’s ordinary shares as reported on the date of grant. […]

After giving effect to the grant of the Warrants described above, warrants to subscribe for an additional 1,611,843 shares of the Company remain available for future grant by the Company’s board of directors pursuant to the Company’s Articles of Association. The foregoing description of the material terms of the Warrants is qualified in its entirety by reference to the Company’s Articles of Association, which is included as Exhibit 1.1 hereto and incorporated by reference herein.

This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336 and 333-282196) of Ascendis Pharma A/S (the “Company” or “Ascendis”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished.

On April 8, 2026, the Company announced that it plans to list its ordinary shares directly on Nasdaq, anticipated to be effective at the opening of trading on April 20, 2026 (the “Effective Date”).

As part of the transition to a direct listing of ordinary shares on The Nasdaq Global Select Market, all outstanding American Depositary Shares (“ADSs”) will be mandatorily exchanged for ordinary shares. Each ADS currently eligible for trading will be exchanged for one ordinary share, which will be listed and commence trading on The Nasdaq Global Select Market under the Company’s existing ticker symbol “ASND” on the Effective Date. The last day of trading of ADSs on Nasdaq is expected to be on April 17, 2026.

On the Effective Date, The Bank of New York Mellon, as Depositary for the ADSs, will call for surrender of all ADSs to be mandatorily exchanged into ordinary shares on the basis of one ordinary share for each ADS held.

Holders of ADSs through the systems of The Depository Trust Company (“DTC”), through a bank, broker or other securities intermediary (“Broker”), will have their ADSs automatically canceled and will automatically receive the ordinary shares through the DTC account of their respective Brokers.

This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336 and 333-282196) of Ascendis Pharma A/S (the “Company” or “Ascendis”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished.

On April 8, 2026, the Company announced new data demonstrating TransCon hGH accelerated TransCon CNP’s benefits beyond linear growth with substantial improvements in arm span, spinal canal dimensions, and lower limb alignment. The new data are from Week 52 of the ongoing Phase 2 COACH Trial of combination therapy with once-weekly TransCon CNP and once-weekly TransCon hGH in children with achondroplasia. Ascendis previously reported Week 52 COACH results that demonstrated mean annualized growth velocity exceeding the 97th-percentile of average stature children, without compromising safety or tolerability and with no acceleration of bone age.

Unprecedented improvements in arm span observed at Week 52 with TransCon CNP and TransCon hGH combination therapy, a measure highly meaningful to the achondroplasia community, with the mean change from baseline in achondroplasia (“ACH”)-specific arm span Z-scores at Week 52 for TransCon CNP treatment-na&iuml;ve and TransCon CNP-treated children in COACH were +1.02 and +0.66, respectively. The TransCon CNP treatment-na&iuml;ve cohort improved +9.4 cm and the TransCon CNP-treated cohort improved +7.9 cm. By comparison, humeral gain by limb lengthening surgery is approximately 8 cm per arm and carries a high complication risk. 1

Mean of L1-L5 average changes in interpedicular distance (“IPD”) for TransCon CNP treatment-na&iuml;ve and TransCon CNP-treated children on combination therapy in COACH were +1.7 mm and +1.1 mm, respectively, compared to +0.6 mm for children on TransCon CNP monotherapy in ApproaCH. Improvements in IPD offer the potential to reduce nerve compression and pain that can result from a narrowed spinal column.

For the TransCon CNP treatment-na&iuml;ve cohort, the mean change in tibial femoral angle (“TFA”) Z-score was -0.86 with combination therapy at Week 52 in COACH and was -0.47 for TransCon CNP monotherapy at Week 52 in ApproaCH, indicating enhanced straightening of the legs. Children previously treated with long-term TransCon CNP monotherapy for an average of 2.56 years maintained in normal range for TFA Z-score.

This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336 and 333-282196) of Ascendis Pharma A/S (the “Company” or “Ascendis”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished.

On April 6, 2026, the Company announced that YUVIWEL (navepegritide; developed as TransCon &reg; CNP) was granted orphan drug exclusivity by the U.S. Food & Drug Administration (“FDA”) and that YUVIWEL is now commercially available in the United States. YUVIWEL is the first and only once-weekly treatment approved by FDA to increase linear growth in children 2 years of age and older with achondroplasia with open epiphyses and is the only one to provide continuous systemic exposure to CNP over the weekly dosing interval. The orphan drug exclusivity granted to YUVIWEL will run through February 27, 2033.

This report contains forward-looking statements that involve substantial risks and uncertainties. All statements, other than statements of historical facts, included in this report regarding Ascendis’ future operations, plans and objectives of management are forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. Examples of such statements include, but are not limited to, statements relating to the anticipated timing of the orphan drug exclusivity granted to YUVIWEL. Ascendis may not actually achieve the plans, carry out the intentions or meet the expectations or projections disclosed in the forward-looking statements and you should not place undue reliance on these forward-looking statements. Actual results or events could differ materially from the plans, intentions, expectations and projections disclosed in the forward-looking statements. […]

SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Ascendis Pharma A/S Date: April 6, 2026 By: /s/ Michael Wolff Jensen Michael Wolff Jensen Executive Vice President, Chief Legal Officer

INCORPORATION BY REFERENCE This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336 and 333-282196) of Ascendis Pharma A/S (the “Company” or “Ascendis”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished. Closing of Warrant Exercise Window On March 30, 2026, an exercise window closed for the Company’s outstanding warrants exercisable for the Company’s ordinary shares, nominal value DKK 1. […]

SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Ascendis Pharma A/S Date: March 30, 2026 By: /s/ Michael Wolff Jensen Michael Wolff Jensen Executive Vice President, Chief Legal Officer

INCORPORATION BY REFERENCE This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336 and 333-282196) of Ascendis Pharma A/S (the “Company” or “Ascendis”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished. Annual General Meeting Results On March 23, 2026, Ascendis held its Annual General Meeting. […]

Ascendis shareholders re-elected all members of the Board and elected Jean-Jacques Bienaim&eacute; as a new non-executive member of the Board, with the term for each such Board member to expire at the Annual General Meeting of the Company to be held in 2027. Shareholders holding 48,137,709 ordinary shares voted in favor of Albert Cha. Shareholders holding 8,096,333 ordinary shares abstained from voting. Shareholders holding 51,152,715 ordinary shares voted in favor of Lars Holtug. Shareholders holding 5,081,327 ordinary shares abstained from voting. Shareholders holding 55,663,224 ordinary shares voted in favor of Jan M&oslash;ller Mikkelsen. Shareholders holding 570,818 ordinary shares abstained from voting. Shareholders holding 50,392,308 ordinary shares voted in favor of Lisa Jane Morrison. Shareholders holding 5,841,734 ordinary shares abstained from voting. Shareholders holding 55,817,044 ordinary shares voted in favor of William Carl Fairey Jr. […]

SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Ascendis Pharma A/S Date: March 24, 2026 By: /s/ Michael Wolff Jensen Michael Wolff Jensen Executive Vice President, Chief Legal Officer

INCORPORATION BY REFERENCE This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336, 333-211511, 333-216882, 333-223134, 333-225284, 333-256571 and 333-282196) of Ascendis Pharma A/S (the “Company” or “Ascendis”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished. On March 17, 2026, the Company announced positive Week 52 topline results from New InsiGHTS, its Phase 2 randomized, open-label, active-controlled trial in the U.S. investigating the safety, tolerability, and efficacy of once-weekly TransCon hGH (lonapegsomatropin; U.S. […]

Bell J, Parker KL, Swinford RD, et al. J Clin Endocrinol Metab 2010;95(1):167–177. doi:10.1210/jc.2009-0178.

SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Ascendis Pharma A/S Date: March 17, 2026 By: /s/ Michael Wolff Jensen Michael Wolff Jensen Executive Vice President, Chief Legal Officer

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): ☐

INCORPORATION BY REFERENCE This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336, 333-211511, 333-216882, 333-223134, 333-225284, 333-256571 and 333-282196) of Ascendis Pharma A/S (the “Company” or “Ascendis”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished. […]

Forward-Looking Statements This report contains forward-looking statements that involve substantial risks and uncertainties. All statements, other than statements of historical facts, included in this report regarding Ascendis’ future operations, plans and objectives of management are forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. Examples of such statements include, but are not limited to, statements relating to (i) TransCon CNP’s potential as a transformative once-weekly treatment option for children with achondroplasia, (ii) the anticipated timing of a regulatory decision by the European Medicines Agency, (iii) Ascendis’ ability to apply its TransCon technology platform to make a meaningful difference for patients, and (iv) Ascendis’ ability to apply TransCon to develop new therapies that demonstrate best-in-class potential to address unmet medical needs. […]

SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Ascendis Pharma A/S Date: March 16, 2026 By: /s/ Michael Wolff Jensen Michael Wolff Jensen Executive Vice President, Chief Legal Officer

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): ☐

INCORPORATION BY REFERENCE This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336 and 333-282196) of Ascendis Pharma A/S (the “Company”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished. Warrant Grants On March 10, 2026, the Company’s board of directors granted an aggregate of 22,480 warrants to certain employees of the Company (the “Warrants”) under the terms of Appendix 1a to the Company’s Articles of Association. […]

SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Ascendis Pharma A/S Date: March 11, 2026 By: /s/ Michael Wolff Jensen Michael Wolff Jensen Executive Vice President, Chief Legal Officer

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): ☐

INCORPORATION BY REFERENCE This report on Form 6-K shall be deemed to be incorporated by reference into the registration statements on Form S-8 (Registration Numbers 333-203040, 333-210810, 333-211512, 333-213412, 333-214843, 333-216883, 333-228576, 333-254101, 333-261550, 333-270088, 333-277519, 333-281916, 333-285322 and 333-293854) and Form F-3 (Registration Numbers 333-209336, 333-211511, 333-216882, 333-223134, 333-225284, 333-256571 and 333-282196) of Ascendis Pharma A/S (the “Company” or “Ascendis”) (including any prospectuses forming a part of such registration statements) and to be a part thereof from the date on which this report is filed, to the extent not superseded by documents or reports subsequently filed or furnished. On February 27, 2026, the Company announced that the U.S. Food & Drug Administration (“FDA”) has granted approval under the FDA’s Accelerated Approval Program for YUVIWEL &reg; (navepegritide; developed as TransCon &reg; […]

Savarirayan R, McDonnell C, Bacino CA, et al. JAMA Pediatr 2026;180(1):18–25. Published online November 17, 2025. doi:10.1001/jamapediatrics.2025.4771

Ascendis makes, including, without limitation: dependence on third-party manufacturers, distributors, and service providers for Ascendis’ products and product candidates; risks related to regulatory review and approval, including the possibility of delays, requests for additional data or analyses, restrictions or limitations on use, approval with labeling that is more limited than expected, or failure to obtain approval in the United States, European Union, or other jurisdictions; clinical development risks, including that results from ongoing or future trials may not confirm earlier data; unforeseen safety or efficacy findings in development programs or on-market products; manufacturing, supply chain, quality, or logistics issues that could delay development or commercialization; unforeseen expenses related to commercialization of any approved Ascendis products; unforeseen research and development or selling, general and administrative expenses and other costs impacting Ascendis’ business generally; […]

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): ☐

Furnished as Exhibit 99.1 to this Report on Form 6-K is the convening notice for the Annual General Meeting of Ascendis Pharma A/S (the “Company”), providing notice to the Company’s shareholders of the Company’s Annual General Meeting to be held on March 23, 2026 at 2:00 pm CET. Furnished as Exhibit 99.2 to this Report on Form 6-K is an annual report of the Company for the year ended December 31, 2025, prepared in accordance with the disclosure requirements of the Danish Financial Statements Act. Furnished as Exhibit 99.3 to this Report on Form 6-K is the Sustainability and P-ESG Report of the Company for the year ended December 31, 2025, prepared in accordance with Section 99a (CSR) and Section 99b (Diversity) of the Danish Financial Statements Act. Exhibits Exhibit No. Description 99.1 Convening Notice to Shareholders. […]

SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Ascendis Pharma A/S Date: February 23, 2026 By: /s/ Michael Wolff Jensen Michael Wolff Jensen Executive Vice President, Chief Legal Officer