Inhibrx Biosciences, Inc. filings document the regulatory record of a clinical-stage biopharmaceutical company with two principal clinical programs, ozekibart (INBRX-109) and INBRX-106. Form 8-K reports furnish financial results, Regulation FD presentations, and clinical updates covering oncology studies in chondrosarcoma, colorectal cancer, Ewing sarcoma, head and neck squamous cell carcinoma, and non-small cell lung cancer.
The company’s proxy materials describe annual meeting matters, board elections, executive compensation and equity incentive governance. Its filings also identify Inhibrx Biosciences as an emerging growth company and provide formal disclosures on operating results, pipeline development, capital resources, risk factors, and the completed 2024 separation from Inhibrx, Inc.
Inhibrx Biosciences, Inc. common stock was the subject of an amended ownership report by Bank of America Corporation and its wholly owned subsidiaries, which reported beneficial ownership of 357,318 shares, or 2.4% of the class. The group reported shared voting power over 357,306 shares and shared dispositive power over 357,318 shares, with no sole voting or dispositive power. The ownership calculation used 14,717,660 shares outstanding as of August 7, 2026, as disclosed in the issuer’s Form 10-Q.
Inhibrx Biosciences, Inc. Chief Executive Officer Mark Lappe reported that the Lappe Family Trust and Lappe Descendants’ Trust purchased 10,040 shares of common stock on October 14, 2026. The Family Trust purchased 2,470 shares at a weighted-average price of $84.0707 and another 2,470 at $84.9992, plus 100 shares at $85.7600. The Descendants’ Trust purchased 2,449 shares at $84.0707, 2,451 at $84.9992, and 100 at $85.7600. Lappe may be deemed to indirectly beneficially own the trust-held shares. No Rule 10b5-1 plan is reported.
Inhibrx Biosciences, Inc. (INBX) CEO and director Mark P. Lappe reported that the Lappe Family Trust, of which he is a trustee, purchased 10,000 common shares on September 25 and 28, 2026. The four weighted-average prices were $98.8659 (3,324 shares), $99.5988 (2,176), $98.8803 (1,500) and $101.7020 (3,000). No Rule 10b5-1 plan is reported. Separately listed indirect holdings as of September 25, 2026, were 165,000 shares in Lappe Descendants' Trust and 54,865 in the Mark Paul Lappe Roth IRA.
Inhibrx Biosciences, Inc. (INBX) updated its corporate presentation on its clinical pipeline. In its randomized head and neck squamous cell carcinoma (HNSCC) study, INBRX-106 plus pembrolizumab had a confirmed objective response rate of 48.3% versus 26.5% with pembrolizumab alone. Six-month progression-free survival (PFS) was 72.4% versus 42.8%, and median PFS was 9.6 versus 4.9 months; median PFS remained maturing at the August 19, 2026 data cutoff.
Among HPV-positive patients, confirmed response rates were 80.0% (8/10) versus 33.3% (3/9), and six-month PFS was 90% versus 33%. An amendment adds 50 HPV-positive patients to Phase 2; the presentation describes a potential accelerated-approval path by end of 2028/early 2029. Any Grade ≥3 adverse events occurred in 58.1% versus 47.1%, and treatment discontinuations were 35.5% versus 14.7%.
Ozekibart met its primary endpoint in the chondrosarcoma registrational trial: median PFS was 5.52 versus 2.66 months (hazard ratio 0.479) and disease-control rate was 54.0% versus 27.5%; data cutoff September 30, 2025. In a Phase 1/2 colorectal cohort, 45 evaluable patients had a 20% objective response rate and 87% disease-control rate. The candidates discussed are investigational and not commercially available.
The Jon F. Kayyem and Paige Gates-Kayyem Family Trust purchased 5,000 common shares of Inhibrx Biosciences, Inc. (INBX) at $100 per share on September 23, 2026, bringing its reported holdings to 434,360 shares. Director Jon Faiz Kayyem disclaims beneficial ownership of the trust shares except to the extent of any indirect pecuniary interest in his distributive shares.
Other listed indirect positions included 250,000 shares in each of the Jon Faiz Kayyem Revocable Trust and Paige Gates-Kayyem Revocable Trust, and 69,843 shares in each custodial account for Child A and Child B. Kayyem disclaims beneficial ownership of the children's account shares except to the extent of any indirect pecuniary interest in his distributive shares.
Inhibrx Biosciences, Inc. (INBX) reports that director Douglas Forsyth received a grant of 10,000 stock options on June 3, 2026, as corrected in this amended Form 4. The options have an exercise price of $95.22 per share and cover 10,000 shares of common stock.
The options become fully exercisable on June 3, 2027, subject to Mr. Forsyth’s continued service through that date, and expire on June 3, 2036. Following this grant, Mr. Forsyth holds 10,000 options directly. No Rule 10b5-1 trading plan is reported in connection with this grant.
Inhibrx Biosciences, Inc. (INBX) reports that director Kristiina Vuori, MD received a grant of 10,000 stock options on June 3, 2026, each with an exercise price of $95.22 and expiring on June 3, 2036. The option becomes fully exercisable on June 3, 2027, subject to her continued service, and this amended filing corrects the original option amount reported.
Inhibrx Biosciences, Inc. reported that director Kimberly Manhard received a grant of 10,000 stock options on June 3, 2026. The options have an exercise price of $95.22 per share, become fully exercisable on June 3, 2027 subject to continued service, and expire on June 3, 2036. This amended report corrects the number of options originally disclosed and shows Manhard holding 10,000 options after the grant; the filing states the transactions were not made under a Rule 10b5-1 trading plan.
Inhibrx Biosciences, Inc. (INBX) reports that director Jon Faiz Kayyem received a corrected grant of 10,000 stock options on June 3, 2026, at an exercise price of $95.22 per share. These options become fully exercisable on June 3, 2027, and expire on June 3, 2036, with 10,000 options held directly after the grant. The amended Form 4 restates a prior filing to correct the number of options granted, and no Rule 10b5-1 trading plan is reported.
Inhibrx Biosciences, Inc. (INBX) director Jon Faiz Kayyem reported an open-market purchase of 5,000 shares of common stock on September 16, 2026 at $100 per share, made indirectly through The Jon F. Kayyem and Paige Gates-Kayyem Family Trust. Following this transaction, that trust holds 429,360 shares. Additional indirect holdings reported include 250,000 shares held by the Jon Faiz Kayyem Revocable Trust, 250,000 shares held by the Paige Gates-Kayyem Revocable Trust, and 69,843 shares held in a custodial account for each of two minor children, for which the reporting person disclaims beneficial ownership in certain cases except to the extent of any indirect pecuniary interest.