AnaptysBio slumps as imsidolimab ACORN Phase II trial fails

Shares of US clinical-stage biotech AnaptysBio (Nasdaq: ANAB) fell as much as 13% in after-hours trading Monday, as it announced that top-line data from its Phase II clinical trial of imsidolimab, formerly known as ANB019, for the treatment of moderate-to-severe acne, also known as the ACORN trial, did not demonstrate efficacy over placebo on primary or secondary endpoints.

AnaptysBio continues to advance three wholly-owned pipeline programs through clinical development. While clinical development is being discontinued in acne, imsidolimab demonstrated efficacy and safety in the GALLOP Phase II trial in generalized pustular psoriasis (GPP) and enrollment of the GEMINI-1 GPP Phase III trial is ongoing and top-line data from the imsidolimab HARP Phase II trial in moderate-to-severe hidradenitis suppurativa is anticipated during the second half of 2022.

Beyond imsidolimab, enrollment is ongoing in the AZURE Phase II trial of rosnilimab, a PD-1 agonist antibody, in moderate-to-severe alopecia areata and healthy volunteer Phase I top-line data for ANB032, a BTLA modulator antibody, is anticipated in the second quarter of 2022.