Absci has reported positive interim Phase 1 data for ABS-201, an investigational antibody being developed for androgenetic alopecia.

Absci has reported positive interim results from the ongoing Phase 1 HEADLINE study evaluating ABS-201, an investigational antibody targeting the prolactin receptor for the treatment of androgenetic alopecia.

The first-in-human trial has completed four single ascending dose cohorts involving 32 healthy adult volunteers and has now advanced into the multiple ascending dose portion of the study in participants with androgenetic alopecia.

According to interim blinded safety data, ABS-201 appeared to be well tolerated across all dose levels tested, ranging from 150 mg to 1,800 mg administered intravenously. No serious adverse events were reported as of the June 8 data cutoff.

Most treatment-emergent adverse events were mild, with headache the most frequently reported event. One moderate headache was reported in the 900 mg cohort and was considered unlikely to be related to treatment.

Ransi Somaratne, chief medical officer at Absci, said: “We are particularly encouraged by the emerging safety, pharmacokinetic, and immunogenicity profile observed to date.”

He added: “We look forward to further characterizing ABS-201’s clinical profile and potential in the ongoing MAD portion of the HEADLINE trial for AGA, and to initiating a Phase 2 trial for endometriosis later this year.”

The company also reported pharmacokinetic findings suggesting the antibody has an estimated half-life of at least 65 days. If confirmed through ongoing follow-up, this could support a dosing schedule requiring only two or three injections over a six-month period.

No apparent effect of anti-drug antibodies on pharmacokinetics was observed in the interim analysis.

Androgenetic alopecia, commonly known as male-pattern or female-pattern hair loss, affects millions of people worldwide. Current treatment options remain limited, with approved therapies including minoxidil and finasteride providing variable efficacy and carrying potential side effects.

ABS-201 is designed to block signalling through the prolactin receptor, a pathway believed to play a role in hair follicle biology. The programme represents a novel approach to hair loss treatment and is being evaluated for its ability to promote hair regrowth and improve hair density.

The ongoing HEADLINE study is a Phase 1/2a randomised, double-blind, placebo-controlled trial expected to enrol up to 227 participants. In addition to safety and tolerability, investigators are assessing measures including hair count, hair width, pigmentation and patient-reported outcomes.

Absci has initiated the first multiple ascending dose cohort in participants with androgenetic alopecia and expects to report interim proof-of-concept data during the second half of 2026. Full proof-of-concept results are anticipated in early 2027.

The company is also planning to begin a Phase 2 trial of ABS-201 in endometriosis later this year, expanding development of the anti-prolactin receptor antibody beyond hair loss.