Astria's pipeline star reduces hereditary angioedema attacks in early phase 1b/2 data

Astria Therapeutics is planning a phase 3 launch for its star monoclonal antibody after early data demonstrated a favorable safety profile and reduction in attack rates of a rare immune disorder.

The initial phase 1b/2 results, shared Monday morning, assessed Astria’s STAR-0215, a monoclonal antibody inhibitor of plasma kallikrein, among 16 patients with hereditary angioedema (HAE).

The trial, dubbed ALPHA-STAR, is measuring the number of adverse events reported, along with other secondary endpoints like duration and severity of HAE attack. The initial data found STAR-0215 to be generally well tolerated with no serious treatment-emergent adverse events (TEAEs) occurring. No discontinuations were recorded and the two TEAEs reported were both mild: one case of dizziness and one rash at injection site.    

The study includes three dosing cohorts. Participants in the first arm received one 450-mg dose of STAR-0215, while participants in the second group received a 600-mg dose followed by a 300-mg dose three months later, and patients in the final cohort were given a 600-mg dose and then another 600-mg dose a month later.

When evaluating monthly HAE attack rate, the first cohort saw a 92% reduction at a six month follow-up; group two recorded a 96% reduction at 84 days; and cohort three demonstrated a 90% decrease at Day 28. Astria said these findings support chronic dosing two or four times per year.

The phase 1b/2 trial has a primary completion date of September 2025, according to ClinicalTrials.gov.

“The initial results of the ALPHA-STAR trial represent a very exciting step forward in the HAE treatment landscape,” Marcus Maurer, M.D., executive director of the Institute of Allergology at the Universitatsmedizin Berlin, said in a March 25 release.

“STAR-0215 has the potential to help patients manage their disease with a mechanism and modality that they trust, but with a substantially improved dosing regimen and the ability to administer without pain,” Maurer added. “Based on this profile, STAR-0215 has the potential to normalize the lives of people living with HAE.”

With the early results in hand, Astria intends to launch STAR-0215 into phase 3 development by the first quarter of 2025, pending discussions with regulatory agencies. 

To get STAR-0215 to market as fast as possible, Astria wants to focus the potential late-stage program on dosing every three months, immediately followed by a second trial to support label expansion with dosing every six months.

Astrai has its origins in Catabasis Pharmaceuticals. When Catabasis' doomed Duchenne muscular dystrophy drug edasalonexent flamed out in phase 3, the company rebranded in 2021 and shifted focus to STAR-0215.