AbCellera Biologics (ABCL) Study result summary

Study design and patient population

• Randomized, double-blind, placebo-controlled, multicenter Phase II trial in 92 postmenopausal women aged 40–75 with moderate to severe vasomotor symptoms (VMS); baseline characteristics were well-matched and similar to prior studies.

• Patients were randomized 1:1 to receive a single 600 mg subcutaneous dose of ABCL635 or placebo, with once-monthly dosing.

• Study endpoints included VMS frequency, severity, patient-reported outcomes, safety, and pharmacokinetics.

• Baseline VMS frequency was slightly lower and mean age slightly higher than in prior studies.

• Eligibility criteria aligned with prior registrational studies.

Efficacy results

• ABCL635 group showed a mean reduction of 8.8 moderate/severe VMS events per day at week 4 versus 3.5 for placebo (placebo-adjusted difference: 5.3 events; 83% reduction for ABCL635 vs. 33% for placebo).

• Severity scores decreased by 1.4 points for ABCL635 vs. 0.3 for placebo (placebo-adjusted difference: 1.1 points; 58% reduction vs. 12% for placebo).

• 37% of ABCL635 patients had complete resolution of moderate/severe VMS, compared to 2.2% for placebo.

• 71% of ABCL635 patients reported symptoms as "much better" at week 4, compared to 16% for placebo; 84% rated symptoms as "Much Better" or "Moderately Better" vs. 27% for placebo.

• Improvements were consistent across subgroups and robust to sensitivity analyses.

Safety and tolerability

• No serious or severe adverse events in the ABCL635 group; placebo group had one serious and two severe events.

• Most common adverse events were headache and fatigue, generally mild and transient; injection site reactions occurred more frequently than in placebo.

• No gastrointestinal toxicity observed with ABCL635; lower incidence of nausea and no diarrhea or abdominal pain.

• No meaningful liver safety signals; one mild, transient case of increased transaminases in ABCL635 group, assessed as unrelated.

• No discontinuations due to adverse events.