# First‐In‐Human Study to Assess the Pharmacokinetics and Safety of DS‐6016a After Single Subcutaneous Injection in Healthy Japanese Adults

## TL;DR

This study tested a new antibody in healthy adults to assess how it behaves in the body and its safety.

## Contribution

The first-in-human evaluation of DS-6016a's pharmacokinetics and safety in healthy Japanese adults.

## Key findings

- DS-6016a showed acceptable safety with no severe adverse events at doses up to 1000 mg.
- Exposure to DS-6016a increased more than proportionally with dose.
- Ferritin levels decreased significantly with treatment, but no dose-related changes in serum iron were observed.

## Abstract

Fibrodysplasia ossificans progressiva is a rare, progressive autosomal dominant genetic disease caused by an activin receptor‐like kinase 2 (ALK2) mutation with a need for effective prophylactic therapies. This single‐center, randomized, double‐blind, placebo‐controlled study evaluated the pharmacokinetics and safety of DS‐6016a, a novel humanized monoclonal anti‐ALK2 antibody, in healthy Japanese adults. In each of the 5–1000 mg DS‐6016a or placebo single subcutaneous dose cohorts, eight male participants were randomly assigned at a 3:1 ratio. DS‐6016a had median times to maximum plasma concentration of 144–240 h and elimination half‐lives of 391–844 h. The increase in DS‐6016a exposure was greater than dose‐proportional across the dose range of 5–1000 mg. The incidence of study drug‐related treatment‐emergent adverse events (TEAEs) was 17% in the placebo group and 11% across all DS‐6016a groups; all were mild and resolved without treatment. No deaths, serious or severe TEAEs, or TEAEs leading to study discontinuation were reported. Ferritin showed a statistically significant dose‐dependent decrease from baseline, while serum iron showed no clear dose‐dependency. No relationship was observed between DS‐6016a dose and the development of anti‐drug antibodies. DS‐6016a had an acceptable safety profile at single subcutaneous doses of 5–1000 mg.