TransCon™ CNP (navepegritide) ApproaCH Trial Topline Results September 16, 2024 TransCon CNP is an investigational product candidate. For investor communication only. Not for use in product promotion. Not for further distribution. Exhibit 99.1

Cautionary Note on Forward-Looking Statements This presentation contains forward-looking statements. All statements other than statements of historical facts contained in this presentation, such as statements regarding our expected timing for submission of certain regulatory filings related to TransCon CNP; our expectations regarding TransCon CNP’s potential to meet the need for a treatment addressing the health and quality-of-life complications of achondroplasia; our development plans for TransCon CNP; our ability to apply our TransCon technology platform to build a leading, fully integrated biopharma company, particularly in the treatment of skeletal dysplasias and growth disorders; plans and objectives of management for future operations and commercialization activities; and future results of current and anticipated products and product candidates, are forward-looking statements. These forward-looking statements are based on our current expectations and beliefs, as well as assumptions concerning future events. These statements involve known and unknown risks, uncertainties and other factors that could cause our actual results to differ materially from the results discussed in the forward-looking statements. These risks, uncertainties and other factors are more fully described in our reports filed with or submitted to the Securities and Exchange Commission (SEC), including, without limitation, our most recent Annual Report on Form 20-F filed with the SEC on February 7, 2024, particularly in the sections titled “Risk Factors” and “Operating and Financial Review and Prospects.” In light of the significant uncertainties in our forward-looking statements, you should not place undue reliance on these statements or regard these statements as a representation or warranty by us or any other person that we will achieve our objectives and plans in any specified timeframe, or at all. Any forward-looking statement made by us in this presentation speaks only as of the date of this presentation and represents our estimates and assumptions only as of the date of this presentation. Except as required by law, we assume no obligation to update these statements publicly, whether as a result of new information, future events, changed circumstances or otherwise after the date of this presentation. This presentation concerns anticipated products that are under clinical investigation and which have not yet been approved for marketing by the U.S. Food and Drug Administration or any other foreign regulatory authority. These anticipated products are currently limited by Federal law to investigational use, and no representation is made as to their safety or effectiveness for the purposes for which they are being investigated. TransCon CNP is an investigational product candidate. For investor communication only. Not for use in product promotion. Not for further distribution. © 2024 Ascendis Pharma. Ascendis, Ascendis Pharma, the Ascendis Pharma logo, the company logo, TransCon, and SKYTROFA® are trademarks owned by the Ascendis Pharma group.

Executive Summary The pivotal ApproaCH Trial in children aged 2-11 years achieved primary objective TransCon CNP demonstrated AGV superior to placebo with LS mean treatment difference of 1.49 cm/year at Week 52 (p<0.0001) For children aged 5-11 years TransCon CNP demonstrated a change from baseline AGV superior to placebo with LS mean treatment difference of 1.78 cm/year at Week 52 (p<0.0001) Children with achondroplasia treated with TransCon CNP exceeded growth rate of general population, providing catch-up growth without accelerated bone age Other endpoints supportive that TransCon CNP may provide benefits beyond linear growth Treatment with TransCon CNP resulted in numerical improvements in health-related quality of life compared to placebo as observed in several ACEM domains Patients dosed with TransCon CNP demonstrated statistical improvement in body proportionality compared to baseline TransCon CNP was generally well-tolerated, with low frequency of mild injection site reactions Continued to show safety results similar to placebo and was well-tolerated, with generally mild TEAEs No evidence of hypotensive effect Injections were generally well tolerated, with low frequency of injection site reactions (0.41 events per patient year), all mild Once-weekly TransCon CNP has potential to address the needs for an efficacious, safe, tolerable, and convenient treatment TransCon CNP is an investigational product candidate. For investor communication only. Not for use in product promotion. Not for further distribution. Data on file, Ascendis Pharma 2024.

ApproaCH Pivotal Trial Design: TransCon CNP in Children with Achondroplasia Ages 2 to 11 years Double-blind, placebo-controlled trial with an open-label extension period 84 children (ages 2 to 11 years) with achondroplasia randomized 2:1 (TransCon CNP:Placebo) 57 Participants TransCon CNP 100 µg/kg/wk TransCon CNP 100 µg/kg/wk 27 Participants Placebo TransCon CNP 100 µg/kg/wk Week 52 Week 104 Double-Blind Period Open-Label Extension Period Primary Objective Evaluate efficacy of TransCon CNP on annualized growth velocity (AGV) Secondary Objective Evaluate efficacy of TransCon CNP on height Z-score Evaluate impact of TransCon CNP on health-related QoL Safety Objective Evaluate safety & tolerability of TransCon CNP Sample Size and Stratification 84 randomized participants, stratified by age and sex (aged < 5 years, aged ≥ 5 years and female, aged ≥ 5 years and male) Countries United States, Canada, Denmark, Ireland, Spain, United Kingdom, Australia, New Zealand Primary Endpoint Annualized growth velocity (AGV) at Week 52 Secondary Endpoints Change from baseline in height Z-score at Week 52 Change from baseline in SF-10 physical summary score at Week 52 Change from baseline in ACEM-PF, ACEM-DF, ACEM-OSM scores at Week 52 Safety Endpoint Incidence of treatment emergent adverse events (TEAEs) and safety assessments Selected Other Endpoints Bone age Upper- to lower-body segment ratio (proportionality) ACEM-EW Muscle functionality test TransCon CNP is an investigational product candidate. For investor communication only. Not for use in product promotion. Not for further distribution.

Demographics and Baseline Characteristics (1/2) Full Analysis Set TransCon CNP (n=57) Placebo (n=27) Overall (N=84) Age (years), mean (SD) 5.6 (2.6) 6.0 (2.7) 5.7 (2.6) Age (years) group, n (%) 2-4 5-7 ≥8 21 (36.8) 26 (45.6) 10 (17.5) 10 (37.0) 10 (37.0) 7 (25.9) 31 (36.9) 36 (42.9) 17 (20.2) Sex, n (%) Female Male 26 (45.6) 31 (54.4) 13 (48.1) 14 (51.9) 39 (46.4) 45 (53.6) Strata (sex, years), n (%) <5 years ≥5 years and female ≥5 years and male 21 (36.8) 17 (29.8) 19 (33.3) 10 (37.0) 8 (29.6) 9 (33.3) 31 (36.9) 25 (29.8) 28 (33.3) Region, n (%) United States Europe Rest of world 14 (24.6) 29 (50.9) 14 (24.6) 8 (29.6) 14 (51.9) 5 (18.5) 22 (26.2) 43 (51.2) 19 (22.6) TransCon CNP is an investigational product candidate. For investor communication only. Not for use in product promotion. Not for further distribution. Data on file, Ascendis Pharma 2024.

Demographics and Baseline Characteristics (2/2) Full Analysis Set TransCon CNP (n=57) Placebo (n=27) Overall (N=84) Height (cm), mean (SD) 88.9 (12.9) 89.1 (11.5) 89.0 (12.4) ACH-specific height Z-score*, mean (SD) 0.18 (0.92) -0.11 (0.73) 0.09 (0.87) CDC (general population) height Z-score**, mean (SD) -4.90 (0.98) -5.21 (0.93) -5.00 (0.97) Weight (kg), mean (SD) 17.8 (6.9) 16.8 (4.6) 17.5 (6.3) BMI (kg/m2), mean (SD) 21.7 (2.7) 20.9 (2.8) 21.4 (2.7) Genetic variant causing achondroplasia, n (%) 1138G>A 1138G>C Other 54 (94.7) 3 (5.3) 0 24 (88.9) 0 3 (11.1) 78 (92.9) 3 (3.6) 3 (3.6) Age at ACH diagnosis (years), n (%) Pre-birth At birth ≥0 to 6 months ≥6 to 12 months ≥12 months 15 (26.3) 20 (35.1) 18 (31.6) 2 (3.5) 1 (1.8) 9 (33.3) 6 (22.2) 9 (33.3) 3 (11.1) 0 24 (28.6) 26 (31.0) 27 (32.1) 5 (6.0) 1 (1.2) Well balanced between key baseline demographics such as height, sex, and age TransCon CNP is an investigational product candidate. For investor communication only. Not for use in product promotion. Not for further distribution. Data on file, Ascendis Pharma 2024. *Hoover-Fong JE, et al. US. Orphanet J Rare Dis. 2021;16(1):522. **https://www.cdc.gov/nccdphp/dnpao/growthcharts/index.htm

Overview of Treatment Emergent Adverse Events (TEAEs) Safety analysis set TransCon CNP (n=57) n (%) Placebo (n=27) n (%) Any Adverse Event Grade 1 Grade 2 Grade 3 Grade 4 Grade 5 52 (91%) 52 (91%) 16 (28%) 4 (7%) 0 0 26 (96%) 25 (93%) 11 (41%) 1 (4%) 0 0 Any treatment-related adverse events 12 (21%) 7 (26%) Serious adverse events 3 (5%) 3 (11%) Adverse events of special interest Injection site reactions Fractures Symptomatic hypotension 11 (19%) 11 (19%) 0 0 4 (15%) 4 (15%) 0 0 AE leading to discontinuation of study drug AE leading to withdrawal from trial AE leading to death 0 0 0 0 0 0 Safety and tolerability results comparable to placebo, with generally mild TEAEs TransCon CNP is an investigational product candidate. For investor communication only. Not for use in product promotion. Not for further distribution. Data on file, Ascendis Pharma 2024.

TransCon CNP Safety and Tolerability Results TransCon CNP showed safety results comparable to placebo and was generally well tolerated, with generally mild TEAEs Majority of AEs were mild (Grade 1) or moderate (Grade 2) and typical for children of these ages No AEs led to discontinuation of TransCon CNP or withdrawal from the trial and no SAEs were assessed as related to TransCon CNP No deaths were reported No fractures or other bone-related safety events observed No evidence of hypotensive effect with TransCon CNP Injections were generally well tolerated, with low frequency of injection site reactions (0.41 events per patient year), all mild TransCon CNP is an investigational product candidate. For investor communication only. Not for use in product promotion. Not for further distribution. Data on file, Ascendis Pharma 2024.

Primary Endpoint: Annualized Growth Velocity at Week 52 TransCon CNP achieved the primary objective, demonstrating superiority over placebo ANCOVA model. TransCon CNP (n=57) Placebo (n=27) LS Mean AGV (cm/yr) at Week 52 5.89 4.41 LS Mean Difference [95% CI] (TransCon CNP vs. Placebo) 1.49 [1.05, 1.93] p-value (TransCon CNP vs. Placebo) p <0.0001 TransCon CNP is an investigational product candidate. For investor communication only. Not for use in product promotion. Not for further distribution. Data on file, Ascendis Pharma 2024.

3.95 5.95 3.75 4.29 Observed Annualized Growth Velocity Over 52 Weeks Children treated with TransCon CNP increased their AGV 2.00 cm/year over 52 weeks (Observed values) Annualized Growth Velocity (cm/year) Mean (±SE) TransCon CNP is an investigational product candidate. For investor communication only. Not for use in product promotion. Not for further distribution. Data on file, Ascendis Pharma 2024.

TransCon CNP demonstrated superior AGV compared to placebo in both age groups Sub-Group Analyses: Primary Endpoint by Age Groups ANCOVA model. Sub-group analyses by age 2 to <5 years 5-11 years TransCon CNP (n=21) Placebo (n=10) TransCon CNP (n=36) Placebo (n=17) LS Mean AGV (cm/yr) at Week 52 6.07 5.06 5.79 4.02 LS Mean Difference [95% CI], p-value (TransCon CNP vs. Placebo) 1.02 [0.29, 1.74] 1.78 [1.22, 2.33] p-value (TransCon CNP vs. Placebo) p=0.0084 p<0.0001 TransCon CNP is an investigational product candidate. For investor communication only. Not for use in product promotion. Not for further distribution. Data on file, Ascendis Pharma 2024. ANCOVA model.

TransCon CNP demonstrated significant change from baseline AGV compared to placebo by age group Sub-Group Analyses: Change from Baseline AGV by Age Group ANCOVA model. Sub-group analyses by age 2 to <5 years 5-11 years TransCon CNP (n=19) Placebo (n=10) TransCon CNP (n=35) Placebo (n=17) Change from Baseline AGV at Week 52, LS Mean 1.57 0.43 2.29 0.52 Treatment Difference, [95% CI], (TransCon CNP vs. Placebo) 1.15 [0.40, 1.89] 1.78 [1.20, 2.35] p-value (TransCon CNP vs. Placebo) p=0.0047 p<0.0001 TransCon CNP is an investigational product candidate. For investor communication only. Not for use in product promotion. Not for further distribution. Data on file, Ascendis Pharma 2024. ANCOVA model.

Secondary Endpoint: Change from Baseline in Height Z-score at Week 52 ACH Height Z-Score TransCon CNP (n=57) Placebo (n=27) LS Mean CFB at Week 52 0.30 0.01 LS Mean Difference [95% CI] (TransCon CNP vs. Placebo) 0.28 [0.18, 0.39] p-value (TransCon CNP vs. Placebo) <0.0001 CDC Height Z-score TransCon CNP (n=55) Placebo (n=27) LS Mean CFB at Week 52 0.15 -0.15 LS Mean Diff [95% CI] (TransCon CNP vs. Placebo) 0.30 [0.14, 0.45] p-value (TransCon CNP vs. Placebo) 0.0003 TransCon CNP achieved secondary objective demonstrating superiority over placebo TransCon CNP is an investigational product candidate. For investor communication only. Not for use in product promotion. Not for further distribution. Data on file, Ascendis Pharma 2024. ANCOVA model.

Change from Baseline in Height Z-score Over 52 Weeks ACH* Height Z-score CDC** Height Z-score Children with achondroplasia treated with TransCon CNP exceeded growth rate of general population, providing catch-up growth without accelerated bone age Change from Baseline Mean (±SE) Change from Baseline Mean (±SE) Visit Visit TransCon CNP is an investigational product candidate. For investor communication only. Not for use in product promotion. Not for further distribution. Data on file, Ascendis Pharma 2024. *Hoover-Fong JE, et al. US. Orphanet J Rare Dis. 2021;16(1):522. **https://www.cdc.gov/nccdphp/dnpao/growthcharts/index.htm

Results Beyond Linear Growth In the total trial population, treatment with TransCon CNP resulted in numerical improvements in health-related quality of life compared to placebo as observed in several ACEM domains At baseline, parents of children generally reported lower burden of health-related quality of life compared to the ACcomplisH Trial Selected endpoints beyond linear growth: Health-related signs and symptoms and quality of life measures: ACEM-OSM, -PF, -DL, -EW and SF-10 PHS Muscle functionality testing (exploratory endpoint) Predefined sub-group analyses of ACEM-Physical Functioning demonstrated potential treatment effect, supported by muscle functionality test results ACEM: Achondroplasia Child Experience Measure, -OSM: Observable Signs Measure, -PF: Impact Physical Functioning, -DL: Impact Daily Living Functioning, -DW:Impact Emotional-Wellbeing, SF-10 PHS: SF-10 Health Survey for Children Physical Summary Score For children with health-related QoL burden at baseline a potential treatment effect was observed across several HRQoL domains of the ACEM measures TransCon CNP is an investigational product candidate. For investor communication only. Not for use in product promotion. Not for further distribution.

n Δ Least Squares Means TransCon CNP Placebo 28 13 -9.80 29 12 -7.49 45 24 -3.36 24 11 -9.96 Results in Patients with Reported Health-Related QoL Burden at Baseline* TransCon CNP Better Placebo Better ACEM Observable Signs Measure ACEM Physical Functioning ACEM Daily Living Functioning ACEM Emotional Well-Being Δ Least Squares Means (95% CI) p=0.05 *Post hoc analysis of data with baseline scores at or above 20. Nominal p-value. TransCon CNP is an investigational product candidate. For investor communication only. Not for use in product promotion. Not for further distribution. Data on file, Ascendis Pharma 2024. TransCon CNP Better Placebo Better Δ Least Squares Means (95% CI) Total Trial Population Patients with HRQoL Burden ≥20 at Baseline*

n Δ Least Squares Means TransCon CNP Placebo 20 10 -11.1 Results in ACEM-PF Predefined Sub-Group Are Supported by Exploratory Muscle Functionality Endpoint TransCon CNP Better Placebo Better ACEM Physical Functioning ˂5 years p=0.037 *Week 52 Body-weight normalized torque in Knee Extension test [N*m/kg]; Exploratory end-point in trial subjects ≥5years at testing. Sub-group age at testing. Nominal p-values. n Δ Least Squares Means TransCon CNP Placebo 24 7 0.20 Placebo Better TransCon CNP Better Muscle Strength* 5-8 years Δ Least Squares Means (95% CI) Δ Least Squares Means (95% CI) p=0.012 TransCon CNP is an investigational product candidate. For investor communication only. Not for use in product promotion. Not for further distribution. Data on file, Ascendis Pharma 2024.

ApproaCH Body Proportionality Patients dosed with TransCon CNP demonstrated statistical improvement in body proportionality compared to baseline (p=0.02) while placebo was unchanged from baseline (p=0.43) Upper to Lower Body Segment Ratio (Change from Baseline) Mean (±SE) TransCon CNP is an investigational product candidate. For investor communication only. Not for use in product promotion. Not for further distribution. Nominal p-value. Data on file, Ascendis Pharma 2024. TransCon CNP Placebo

Summary & Next Steps The pivotal ApproaCH Trial results support the desired target product profile of once-weekly TransCon CNP delivering continuous exposure of CNP Plan to submit New Drug Application to the U.S. FDA for TransCon CNP for treatment of children with achondroplasia in the first quarter of 2025 Plan to submit a Marketing Authorisation Application for treatment of children with achondroplasia to the European Medicines Agency during the third quarter of 2025 Comprehensive development plans continue with ongoing and planned trials to support TransCon CNP in additional patient populations Strong retention with all 82 children who completed the double-blind period are continuing in the open-label extension of ApproaCH With once-weekly SKYTROFA and TransCon CNP, Ascendis is uniquely positioned to become the leader in treatment of skeletal dysplasias and growth disorders TransCon CNP is an investigational product candidate. For investor communication only. Not for use in product promotion. Not for further distribution.

Vision 2030 Be the Leading Endocrinology Rare Disease Company  Achieve blockbuster status (>$1B) for TransCon PTH, TransCon hGH, and TransCon CNP through worldwide commercialization Be the leader in Growth Disorders and Hypoparathyroidism, pursuing clinical conditions, innovative LCM and complementary patient offerings Expand pipeline with Endocrinology Rare Disease blockbuster product opportunities Create Value in Additional Therapeutic Areas through Innovative Business Models Obtain accelerated approval in oncology with registrational trials ongoing Pursue TransCon product opportunities in >$5B indications Maximize value creation of these product opportunities through collaboration with therapeutic area market leaders Differentiate with Ascendis Fundamentals Outperform industry drug development benchmarks with Ascendis’ product innovation algorithm Remain independent as a profitable biopharma through lean and flexible ways of working Let our values Patients, Science, Passion drive our decisions to success Achieve blockbuster status for multiple products and expand our engine for future innovation TransCon CNP is an investigational product candidate. For investor communication only. Not for use in product promotion. Not for further distribution.