Q32 Bio Inc.

OrbiMed Advisors LLC and affiliated entities filed Amendment No. 4 to their Schedule 13D on Q32 Bio Inc. (QTTB), triggered July 16, 2026. OrbiMed Advisors holds 4,127,987 shares (13.9%) in aggregate; subsidiary OrbiMed Capital GP VII LLC holds 3,502,987 shares (11.8%) and OrbiMed Genesis GP LLC holds 625,000 shares (2.1%). The specific purpose or event triggering this amendment is not captured in the available excerpt, but OrbiMed is a specialist healthcare investor; a fourth amendment from a 13.9% holder warrants attention for any shift in intent toward the biotech.

Q32 Bio filed an S-3 shelf registration statement to register securities for future capital raises. As a clinical-stage biotech developing complement-mediated disease therapies, the shelf provides flexibility to raise capital quickly to fund drug development. Standard capital markets preparedness filing.

Q32 Bio (QTTB) entered into an underwriting agreement for a public offering of 10,958,904 shares of common stock at $18.25 per share, plus pre-funded warrants to purchase 4,931,506 shares at $18.2499 per warrant, on July 15, 2026. The underwriters have a 30-day option to purchase up to 1,643,835 additional shares. Estimated net proceeds are approximately $187.6 million ($215.8 million if the overallotment is exercised in full), intended for working capital and research and development. Closing was expected on approximately July 16, 2026.

Q32 Bio (QTTB) filed a 424B5 prospectus supplement on July 14, 2026, for a public offering of 10,958,904 shares of common stock at $18.25 per share plus 4,931,506 pre-funded warrants at $18.2499 each, with an overallotment option for up to 1,643,835 additional shares. Joint book-running managers are Morgan Stanley, Jefferies, Cantor Fitzgerald, and Oppenheimer & Co.; H.C. Wainwright & Co. is lead manager. Estimated net proceeds are approximately $187.6 million. Proceeds are intended for working capital and R&D activities.

Q32 Bio (QTTB) filed a preliminary 424B5 prospectus supplement on July 13, 2026, for a proposed registered public offering of common stock and pre-funded warrants. Joint book-running managers include Morgan Stanley, Jefferies, Cantor Fitzgerald, and Oppenheimer & Co., with H.C. Wainwright & Co. as lead manager. Offering price and final share count were not yet determined at the time of this preliminary filing. This is the earlier of two 424B5 filings for the same Q32 Bio offering.

Q32 Bio (QTTB) disclosed Phase 2 Part B efficacy data for bempikibart (anti-IL-2Rα antibody) in severe alopecia areata (AA) on July 13, 2026. The study enrolled 33 patients with SALT scores of 50–100 and episode durations of four years or less, of whom 36.4% had prior JAK inhibitor exposure. Treatment consisted of a 200 mg loading dose administered weekly for four weeks followed by a maintenance regimen, continued through 36 weeks. Enrollment exceeded the initial target due to patient demand, and the blinded, sham-controlled study design provides robust evidence for the bempikibart program.

Q32 Bio Inc. filed an S-3 shelf registration statement on June 25, 2026, establishing a framework to sell securities on a delayed or continuous basis under Rule 415. The filing registers unspecified types and amounts of securities. CEO Jodie Morrison is listed as the agent contact. This is a standard shelf registration enabling future capital raises — no specific offering size or timing is determined yet. Administrative capital markets infrastructure; not an immediate dilutive event.

QTTB filed an 8-K Item 5.07 on June 16, 2026 reporting submission of matters to a vote of security holders (annual meeting results). Body unavailable — excerpt contains insufficient narrative to extract specific vote tallies or proposal outcomes.