ACcomplisH: A Phase 2, Multicenter, Double-blind, Randomized, Placebo-controlled, Dose Escalation Trial Evaluating Safety, Efficacy, and Pharmacokinetics of Subcutaneous Doses of TransCon CNP Administered Once Weekly for 52 Weeks in Prepubertal Children With Achondroplasia Followed by an Open-Label Extension Period

Study start date: June 24, 2020

Inclusion Criteria: 1. Clinical diagnosis of ACH with genetic confirmation 2. Age between 2 to 10 years old (inclusive) at Screening Visit 3. Prepubertal (Stage 1 breasts for girls or testicular volume \< 4ml for boys) at Screening Visit 4. Able to stand without assistance 5. Caregiver willing and able to administer subcutaneous injections of study drug Exclusion Criteria: 1. Clinically significant findings at Screening that: * are expected to require surgical intervention during participation in the trial or * are musculoskeletal in nature, such as Salter-Harris fractures and severe hip pain or * otherwise are considered by investigator or Medical Monitor/Medical Expert to make a participant unfit to receive study drug or undergo trial related procedures 2. Have received treatment (\>3 months) of human growth hormone (hGH) or other medications known to affect stature or body proportionality at any time 3. Have received any dose of medications intended to affect stature or body proportionality within the previous 6 months of Screening Visit 4. Have received any study drug or device intended to affect stature or body proportionality at any time 5. History or presence of injury or disease of the growth plate(s), other than Achondroplasia, that affects growth potential of long bones