Adults 15 Months to 12, any sex, with Achondroplasia. Patients with the condition only — healthy volunteers not accepted.
Results — posted to ClinicalTrials.gov
Per-arm endpoint measurements with 95% confidence intervals where reported. Source: trial results section.
Number of Participants With Treatment Emergent Adverse Events (TEAEs), Serious Adverse Events (SAEs) and Severe AEsPrimary· From first dose of study drug up to 28 days after last dose of study drug (maximum up to 11 months)
An AE was any untoward medical occurrence that did not necessarily have a causal relationship with study treatment. TEAE was an AE that occurred after initiation of study treatment that was not present at the time of treatment start or an AE that increased in severity after the initiation of medication, if the event was present at the time of treatment start emerges. SAE was an AE resulting in any of the following outcomes or considered medically significant: death; initial or prolonged inpatient hospitalization; life-threatening experience (immediate risk of dying); persistent or significant
AEs
Group
Value
95% CI
Recifercept 1 Milligram Per Kilogram (mg/kg) Once Weekly
9
Recifercept 2 mg/kg Twice Weekly
11
Recifercept 1.5 mg/kg Once Daily
0
SAEs
Group
Value
95% CI
Recifercept 1 Milligram Per Kilogram (mg/kg) Once Weekly
0
Recifercept 2 mg/kg Twice Weekly
0
Recifercept 1.5 mg/kg Once Daily
0
Number of Participants With Clinically Meaningful Findings in Laboratory Test Parameters Through the StudySecondary· From baseline up to end of study/early termination (for a maximum duration of 11 months)
Laboratory parameters that were assessed included lymphocytes, neutrophils, eosinophils, monocytes and potassium. Clinically significant abnormal laboratory findings were determined based on investigator's decision.
Hematology: Lymphocytes
Group
Value
95% CI
Recifercept 1 Milligram Per Kilogram (mg/kg) Once Weekly
0
Recifercept 2 mg/kg Twice Weekly
1
Recifercept 1.5 mg/kg Once Daily
0
Hematology: Neutrophils
Group
Value
95% CI
Recifercept 1 Milligram Per Kilogram (mg/kg) Once Weekly
0
Recifercept 2 mg/kg Twice Weekly
1
Recifercept 1.5 mg/kg Once Daily
0
Hematology: Eosinophils
Group
Value
95% CI
Recifercept 1 Milligram Per Kilogram (mg/kg) Once Weekly
1
Recifercept 2 mg/kg Twice Weekly
3
Recifercept 1.5 mg/kg Once Daily
0
Hematology: Monocytes
Group
Value
95% CI
Recifercept 1 Milligram Per Kilogram (mg/kg) Once Weekly
2
Recifercept 2 mg/kg Twice Weekly
0
Recifercept 1.5 mg/kg Once Daily
0
Chemistry: Potassium
Group
Value
95% CI
Recifercept 1 Milligram Per Kilogram (mg/kg) Once Weekly
2
Recifercept 2 mg/kg Twice Weekly
1
Recifercept 1.5 mg/kg Once Daily
0
Number of Participants With Clinically Significant Findings in Vital Signs Through the StudySecondary· From baseline up to end of study/early termination (for a maximum duration of 11 months)
Absolute values and changes from baseline in supine systolic and diastolic blood pressure, oral temperature, and pulse rate were planned to be summarized by treatment in accordance with the sponsor reporting standards. Clinically significant abnormal laboratory findings were those which were not associated with the underlying disease, unless judged by the investigator to be more severe than expected for the participant's condition.
Group
Value
95% CI
Recifercept 1 Milligram Per Kilogram (mg/kg) Once Weekly
0
Recifercept 2 mg/kg Twice Weekly
0
Recifercept 1.5 mg/kg Once Daily
0
Number of Participants With Clinically Significant Findings in Physical Examination Through the StudySecondary· From baseline up to end of study/early termination (for a maximum duration of 11 months)
A complete physical examination included cardiovascular, respiratory, gastrointestinal systems, and skin. Height and weight will also be measured and recorded as part of the anthropometric measurements collected. Anthropometric data was collected by appropriately trained individuals at the trial site and in accordance with the anthropometric measurement manual.
Group
Value
95% CI
Recifercept 1 Milligram Per Kilogram (mg/kg) Once Weekly
0
Recifercept 2 mg/kg Twice Weekly
0
Recifercept 1.5 mg/kg Once Daily
0
Number of Participants With Positive Anti-Drug Antibodies (ADA)Secondary· From Month 3 up to end of study/early termination (up to Month 11)
Group
Value
95% CI
Recifercept 1 Milligram Per Kilogram (mg/kg) Once Weekly
12
Recifercept 2 mg/kg Twice Weekly
15
Recifercept 1.5 mg/kg Once Daily
2
Adverse events — posted to ClinicalTrials.gov
Time frame: From first dose of study drug up to 28 days after last dose of study drug (maximum up to 11 months).
Reporting threshold: 5%.
Adverse-event reports describe events observed during the trial — not all are caused by the drug.
All participants who completed the prior study to assess long-term safety, tolerability, pharmacokinetics and efficacy, and in the opinion of the investigator, continue to have a positive risk:benefit profile, will be offered to enroll in this open-label extension (OLE) study for up to an additional 24 months of treatment.
Approximately 63 participants will be offered to continue at the previously received dose of Recifercept either
Low Dose Medium Dose High Dose
or at the therapeutic dose once it is identified.
Participants will attend the clinic monthly for 24 months. Assessments include safety, blood sampling, physical examination, vital signs, anthropometric body measurements \& patient/caregiver quality of life questionnaires.
Publications & conference data
2 peer-reviewed publications reference this trial (live from Europe PMC):
NCT05061277 — Study to Evaluate the Pharmacokinetics, Safety and Tolerability of Recifercept in Healthy Chinese Participants
· Phase 1
· withdrawn
NCT05659719 — A Study to Learn About Recifercept in Patients With Achondroplasia
· completed
NCT04638153 — A Study Of Safety, Tolerability And Effectiveness Of Recifercept In Children With Achondroplasia
· Phase 2
· terminated
NCT04543344 — Study To Evaluate The Pharmacokinetic, Safety And Tolerability Of Single Or Multiple Subcutaneous Doses of Recifercept
· Phase 1
· completed
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Publications: Europe PMC API search by NCT ID, retrieved 10 June 2026
Drug + disease cross-links: matched in real time against Drug Landscape's normalised drug + company + condition tables
Sponsor: as reported to ClinicalTrials.gov by Pfizer
Last refreshed: 8 February 2024
Drug Landscape aggregates and links these public records for informational use only. Always verify against the primary source before clinical or regulatory decisions. Canonical URL: https://druglandscape.com/trial/NCT05116046.