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$ABCL AbCellera’s official abstract for ABCL635 from The Menopause Society 2026 meeting is out. While we already knew the high-level Phase 2 data, this new TMS abstract gives us a deeper look at a few more granular data points: 1) Exact Headache Breakdown (Clustered at the Highest Dose) Prior slides noted mild headache as a common adverse event, but we now have the exact numbers. In the SAD cohort, transient, mild headache occurred in 23.3% (n=7) of participants within the first few days of dosing. Importantly, more than half of those cases (n=4) were clustered at the highest 900mg supratherapeutic dose, well above the 300mg and 600mg doses taken into the multi-dose cohort. 2) Quantified Target Engagement (65% to 80% Testosterone Drop) In Q1 earnings slides, AbCellera showed line graphs of hormone suppression to prove ABCL635 was hitting the target. The abstract puts more hard numbers to those charts: male participants saw a 65% to 80% reduction in testosterone from baseline across the 300mg to 900mg doses (alongside corresponding drops in LH and FSH), confirming strong, concentration-dependent HPG axis suppression. 3) Cohort Demographics The abstract also discloses the exact median ages for the trial groups: 54.5 years for the SAD cohort and 62.0 years for the MAD cohort. Quick recap of the Phase 1/2 core results: • Trial Setup: The Single Ascending Dose (SAD) cohort enrolled 40 healthy men and postmenopausal women (6:2 active-to-placebo across 30mg, 100mg, 300mg, 600mg, and 900mg). The Multiple Ascending Dose (MAD) cohort enrolled 16 healthy postmenopausal women (6:2 active-to-placebo receiving 3 monthly doses of 300mg or 600mg), alongside the Phase 2 proof-of-concept cohort in women with moderate-to-severe VMS. • Clean Safety & Liver Profile: Zero serious or severe adverse events, no dose-limiting toxicities, and (crucially for the NK3R class) no clinically significant liver enzyme elevations across either the SAD or MAD cohorts. • Validated Monthly Dosing (PK): Dose-proportional exposure with a roughly 24-day half-life, backing up the convenient once-every-4-weeks injection schedule. To summarize, the granular numbers reinforce the bull case for ABCL635. We’re seeing potent, quantifiable target engagement at therapeutic doses, a roughly 24-day half-life that easily supports monthly dosing, and a very clean safety profile where even mild side effects like headaches were largely confined to the maxed-out 900mg test dose, all with zero liver toxicity signals.