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 o

Ascendis Pharma A/S 42nd Annual J.P.

Morgan Healthcare Conference January 8, 2024 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 products and prospective product candidates; clinical trial

results; the expected timing of future clinical trial results and feedback from regulatory authorities; the scope, progress, results and costs of developing our product candidates or any other future product candidates; timing and likelihood of

success; 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 16, 2023 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 Ascendis Pharma approved products as well as

Ascendis Pharma investigational product candidates that are or have been under clinical investigation and which have not yet been approved for marketing by the U.S. Food and Drug Administration, European Medicines Agency or other foreign regulatory

authorities. These investigational product candidates are currently limited by law to investigational use, and no representations are made as to their safety or effectiveness for the purposes for which they are being investigated. This presentation

is for investor communication only. Not for use in product promotion. For investor communication only. Not for use in product promotion. Not for further distribution.

Executive Summary Validated TransCon

technology platform and algorithm for product innovation Two approved products - SKYTROFA (TransCon hGH) and YORVIPATH (TransCon PTH) Pivotal data and submission of NDA for TransCon CNP expected in Q4 2024 Oncology portfolio Phase

2 data expected in Q4 2024 Creation of Ophthalmology NewCo, financed by institutional investors, expected in Q1 2024 SKYTROFA achieved U.S. market value leadership in 2023 Expected full year 2023 SKYTROFA revenue of ~ 179 million1 Full year

2024 SKYTROFA revenue expected to be 320 to 340 million2 YORVIPATH first launch in Germany January 2024 Rolling out to Europe Direct and International Markets starting in 2024 In the U.S., PDUFA goal date of May 14, 2024, and

launch expected the following quarter, if approved Business model built on fast, successful drug development and commercial therapeutic synergies Expect to be operating cash flow breakeven on a quarterly basis by the end of 2024 For investor

communication only. Not for use in product promotion. Not for further distribution. 1 Unaudited preliminary estimate. 2 Based on average 2023 exchange rates.

Vision 3x3: Building a Leading Global

Biopharma Company Our goal is to achieve sustainable growth through multiple approaches Obtain regulatory approval for three independent Endocrinology Rare Disease products TransCon hGH for pediatric growth hormone deficiency TransCon

PTH for adult hypoparathyroidism TransCon CNP for achondroplasia Grow Endocrinology Rare Disease pipeline through Global clinical reach Pursuing 9 total indications, label optimization, and life cycle management New endocrinology products

Establish global commercial presence for our Endocrinology Rare Disease area Build integrated commercial organization in North America and select European countries Establish global commercial presence through partners with local expertise and

infrastructure Advance a high-value oncology pipeline with one IND or similar filing each year Create a third independent therapeutic area with a diversified pipeline Ascendis Pharma's 2020 - 2025 strategic roadmap For investor communication

only. Not for use in product promotion. Not for further distribution.

Endocrinology Rare Disease Pipeline

& Ascendis Direct Commercialization For investor communication only. Not for use in product promotion. Not for further distribution.

Endocrinology Rare Disease Products

Approved in Major Markets TransCon hGH Pediatric Growth Hormone Deficiency United States1 Approved in the U.S. as SKYTROFA (lonapegsomatropin-tcgd) European Union2 and Selected Other Countries3 Approved in the EU as SKYTROFA (lonapegsomatropin)

TransCon PTH Adult Chronic Hypoparathyroidism European Union4 and Selected Other Countries5 Approved in the EU as YORVIPATH (palopegteriparatide) First country launch planned in Germany in January 2024 1. SKYTROFA [package insert]. Palo Alto,

CA: Ascendis Pharma Inc. October 2022. 2. SKYTROFA SMPC. Hellerup, Denmark: Ascendis Pharma Inc. January 2022. 3. SKYTROFA is also approved in Norway, Iceland, Lichtenstein and Great Britain (covering England, Wales, Scotland). 4.

YORVIPATH SMPC. Hellerup, Denmark: Ascendis Pharma Inc. November 2023. 5. YORVIPATH is also approved in Norway and Iceland. For investor communication only. Not for use in product promotion. Not for further distribution.

TransCon hGH: Expanding Beyond

Pediatric GHD Pediatric GHD accounts for approximately 50% of the hGH market by patients Growth hormone plays an essential role in the health of children and adults Maintains normal body composition and cardiometabolic health Promotes normal growth

in children Daily hGH is approved for multiple indications in adult and pediatric patients Adult GHD accounts for approximately 10% of the daily hGH market However, fewer than 10% of adults with suspected GHD1 are treated with hGH TransCon hGH Phase

3 foresiGHt Trial in adult GHD Demonstrated superiority to placebo on primary and secondary efficacy endpoints Demonstrated comparable results to daily hGH on primary and secondary endpoints2 Expected sBLA submission in Q2 2024 For investor

communication only. Not for use in product promotion. Not for further distribution. 1 A. Hoffman et al (2023). SAT611 Prevalence Of Comorbidities Among Treated And Untreated Adults With Suspected Growth Hormone Deficiency. Journal of the Endocrine

Society. 7. 10.1210/jendso/bvad114.1344. 2 Exploratory post-hoc analysis for patients with IGF-1 SDS levels 1.75 at Week 38.

SKYTROFA Revenue Development and

Expectations SKYTROFA was launched in U.S. in Q4 2021, Germany in Q3 2023 SKYTROFA Q4 2023 revenue of ~ 64 million* Estimated SKYTROFA U.S. pediatric GHD market penetration exiting 2023 at ~16% Expect full year 2024 SKYTROFA revenue of

320 - 340 million** * Unaudited preliminary estimate. ** Reflects 2024 SKYTROFA revenue expectations announced on Jan. 7, 2024, based on average 2023 exchange rates. For investor communication only. Not for use in product promotion.

Not for further distribution. Quarterly SKYTROFA Revenue (million) Annual SKYTROFA Revenue (million)

TransCon hGH Program Summary and

Outlook Attained U.S. market value leadership in 2023 Completed enliGHten Trial in pediatric GHD1 Majority of patients met or exceeded average parental height SDS Demonstrated the long-term safety in patients treated up to 6 years Planned sBLA

submission to FDA for adult GHD Q2 2024 Topline results from Phase 2 trial in Turner syndrome expected Q4 2024 Expanding reach for SKYTROFA through Ascendis commercial organization building on therapeutic synergies Full year 2024 SKYTROFA revenue

expected to be 320 to 340 million2 For investor communication only. Not for use in product promotion. Not for further distribution. Committed to making TransCon hGH the global leading product in value in a growing growth hormone market

1 Vlachopapadopoulou et al. Poster LB17, presented at ESPE 2023. 2 Based on average 2023 exchange rates.

Myopathy Spondylorthropathy Dry

skin Thinning hair Brittle nails Altered tooth morphology Cataracts Papilledema Anxiety & depression Cognitive impairment ("brain fog") Paresthesia Muscle cramps Pain Tetany Nephrocalcinosis* Nephrolithiasis* Chronic kidney disease*

Vascular calcifications Cardiac arrhythmias Hypocalcemia-associated dilated cardiomyopathy Laryngospasm Seizures Basal ganglia calcifications Parkinsonism or dystonia Hypoparathyroidism: One Disease, Multiple Consequences1-4 CENTRAL NERVOUS SYSTEM

OPHTHALMALOGICAL PERIPHERAL NERVOUS SYSTEM CARDIOVASCULAR DERMATOLOGICAL RENAL NEUROPSYCHIATRIC MUSCULOSKELETAL DENTAL RESPIRATORY Thyroid gland Parathyroid gland Absence or deficiency of parathyroid hormone (PTH) is linked to multi-organ

manifestations5,6 * These manifestations are mostly the result of treatment with calcium supplements and activated vitamin D rather than of the disease itself.5 1. Underbjerg L, Sikjaer T, Mosekilde L, et al. Cardiovascular and renal

complications to postsurgical hypoparathyroidism: a Danish nationwide controlled historic follow-up study. J Bone Miner Res. 2013;28(11):2277-2285. doi:10.1002/jbmr.1979. 2. Underbjerg L, Sikjaer T, Mosekilde L, et al. The

epidemiology of nonsurgical hypoparathyroidism in Denmark: a nationwide case finding study. J Bone Miner Res. 2015;30(9):1738-1744. doi:10.1002/jbmr.2501. 3. Shoback DM, Bilezikian JP, Costa AG, et al. Presentation of

hypoparathyroidism: etiologies and clinical features. J Clin Endocrinol Metab. 2016;101(6):2300-2312. doi:10.1210/jc.2015-3909. 4. Underbjerg L, Sikjaer T, Mosekilde L, et al. The epidemiology of nonsurgical hypoparathyroidism in

Denmark: a nationwide case finding study. J Bone Miner Res. 2015;30(9):1738-1744. doi:10.1002/jbmr.2501. 5. Mannstadt M, Bilezikian JP, Thakker RV, et al. Hypoparathyroidism. Nat Rev Dis Primers. 2017;3:17055.

doi:10.1038/nrdp.2017.55. 6. Shoback DM, Bilezikian JP, Costa AG, et al. Presentation of hypoparathyroidism: etiologies and clinical features. J Clin Endocrinol Metab. 2016;101(6):2300-2312. doi:10.1210/jc.2015-3909. For

investor communication only. Not for use in product promotion. Not for further distribution.

Latest Clinical Practice Guideline

Consider PTH replacement therapy in patients not adequately controlled on conventional therapy Inadequate control is considered to be any one of the following: Symptomatic hypocalcemia Hyperphosphatemia Renal insufficiency Hypercalciuria Poor

quality of life In addition, individuals with poor compliance, malabsorption, or who are intolerant of large doses of calcium and active vitamin D may also benefit from PTH replacement therapy 1. Aliya A Khan et al, The Second International

Workshop on the Evaluation and Management of Hypoparathyroidism, Journal of Bone and Mineral Research, 10.1002/jbmr.4671. For investor communication only. Not for use in product promotion. Not for further distribution.

Significantly Improved Renal

Function with TransCon PTH Treatment in Phase 3 PaTHway Trial Post Hoc Analysis eGFR (an assessment of kidney filtering capacity) was calculated by the trial's central lab using the Modification of Diet in Renal Disease Study Group (MDRD)

equation (Levey, Ann Intern Med 2006). Patients Randomized to TransCon PTH Change in mean eGFR from Baseline (mL/min/1.73m) Patients Randomized to Placebo / Switched to TransCon PTH after Week 26 At Week 26 At Week 26 At Week 52 At Week 52 eGFR <

60 at baseline eGFR 60 at baseline For investor communication only. Not for use in product promotion. Not for further distribution. * * * indicates nominal p<0.05 indicates nominal p<0.001 Data

Europe Direct1 - Germany

~70,000 adults2 with chronic hypoparathyroidism in Germany Launch of YORVIPATH planned in January 2024, initial list price3 of 105,000 per patient per year Europe Direct - other selected countries Over 100,000 additional adults with

chronic hypoparathyroidism Next major market expected end of 2024, expected availability across Europe by end of 2025 Providing commercial product through early access routes, such as named patient,' until commercial reimbursement

established U.S. Over 80,0004 adults with chronic hypoparathyroidism in the U.S. PDUFA date May 14, 2024; expect to launch in Q3 2024, if approved Experienced commercial team in place for rapid, efficient launch Ascendis Commercial Organization -

TransCon PTH Launch For investor communication only. Not for use in product promotion. Not for further distribution. 1 DACH, France & BeNeLux, Iberia, Italy, Nordics, UK & Ireland. 2 German SHI claims data from the Institute for Applied

Health Research Berlin (Institut f r angewandte Gesundheitsforschung Berlin - InGef) research database. 3 Herstellerabgabepreis. 4 U.S. prevalence literature review and epi meta-analysis (Powers, Clarke, Milliman project, ipm.ai claims project;

HCUPnet, Healthcare Cost and Utilization Project. Agency for Healthcare Research and Quality, Rockville, MD. for surgical cohort projection).

TransCon PTH Program Summary and

Outlook Completed two successful Phase 3 trials: PaTHway and PaTHway Japan Post hoc analysis showed significantly improved renal function in TransCon PTH-treated patients Approved in European Union and other territories as YORVIPATH German launch of

YORVIPATH planned in January 2024 Rolling out to Europe Direct and International Markets starting in 2024 In the U.S., PDUFA date of May 14, 2024 U.S. launch of YORVIPATH expected in Q3 2024, if approved Launching TransCon PTH through established,

proven endocrinology rare disease infrastructure For investor communication only. Not for use in product promotion. Not for further distribution.

Current Consensus Updated View

Changing the Treatment Paradigm of Achondroplasia Primary Manifestations Secondary Manifestations Growth disorder Growth disorder Muscle disorder Height ACH-AE HRQoL Muscle Strength/ Stamina Height ACH-AE ACH-AE; Increased incidence of

Achondroplasia-related Adverse Events. HRQoL: Reduced Health-Related Quality of Life; Height; Reduced height. Muscle Strength/Stamina; Reduced muscular functionality, including reduced strength and stamina Address all aspects of achondroplasia for

patients of all ages HRQoL Muscle Strength/ Stamina direct consequence indirect/secondary consequence For investor communication only. Not for use in product promotion. Not for further distribution. TransCon CNP is an investigational product

Growth across full trial population

(n=57) on TransCon CNP 100 g/kg/week for 52 weeks consistent with results from randomized period ANCOVA model. Data on file. Treatment Effect of TransCon CNP 100 g/kg/week, Age 2-10 years TransCon CNP Blinded Period Placebo TransCon CNP

Blinded Period Placebo TransCon CNP incl 1-year OLE 6 mg/kg/week 20 mg/kg/week 50 mg/kg/week 100 mg/kg/week Pooled Placebo 100 mg/kg/week (All ages) 6 mg/kg/week 20 mg/kg/week 50 mg/kg/week 100 mg/kg/week Pooled Placebo 100 mg/kg/week (All ages) N=

AHV (cm/Year) TransCon CNP incl 1-year OLE 10 11 15 57 N= 10 11 10 11 10 11 15 57 TransCon CNP is an investigational product candidate. ACH Height SDS D For investor communication only. Not for use in product promotion. Not for further distribution.

AHV: Annualized height velocity; ACH: achondroplasia; SDS: standard deviation score; OLE: open-label extension.

Health-Related Quality-of-Life

Measures (HRQoL) SF-10 Health Survey for Children A 10-item non-disease specific survey of a child's functional health and well-being.1 Physical measures include assessments of: Limitations in activities, schoolwork Bodily pain or

discomfort Overall health relative to other children Physical coordination or clumsiness Lower scores indicate greater impairment. Validated in children ages 5 yrs and older. Achondroplasia Child Experience Measure A condition-specific clinical

outcome measure that assesses the impact of achondroplasia on a child's health-related quality of life. Includes assessments of:2 Daily Living - Reach objects or high places. Toilet themselves. Bath, shower, wash. Perform fine motor

skill tasks. Emotional Well-Being - Feeling different, frustrated, etc. Physical Functioning - Sit for long periods of time. Climb stairs. Be physically active. Walk long distances. Run. School - Difficulty participating. Limited

or modified gym class participation. Missed school. The measure is scored on a 0-100 scale, with higher scores indicating greater impairment. 1. SF-10 Health Survey for Children | QualityMetric Accessed 28 December 2023. 2. ACEM-Impact |

Achondroplasia Child Experience Measure - Impact described in ePROVIDE (mapi-trust.org) Accessed 28 December 2023. For investor communication only. Not for use in product promotion. Not for further distribution. TransCon CNP is an investigational

Achondroplasia Child Experience

Measure Consistent Positive Treatment Effect Across HRQoL Domains SF-10 Physical Summary LS mean difference to placebo (95%CI) by ANCOVA LS mean difference to placebo (95%CI) by ANCOVA Placebo better 100 g/kg better Placebo better 100 g/kg

better Placebo n= 100 g/kg/week n= 13 14 5 9 13 16 9 13 13 16 6 12 p=0.002 p=0.047 p=0.045 Patients dosed with TransCon CNP demonstrated HRQoL improvements in multiple domains compared to placebo TransCon CNP is an investigational product

candidate. For investor communication only. Not for use in product promotion. Not for further distribution. All participants in blinded or OLE period of ACcomplisH who were initiated directly on 100 g/kg/week treatment (total n=19) compared to

all participants from blinded period receiving placebo (n=15). All domains are missing some data points. Nominal p-values. Data on file.