NKTX Nkarta Inc

Item. 8.01 Other Events.

On June 27, 2023, the Company announced updated clinical data from its ongoing Phase 1 study of NKX101 to treat patients with relapsed or refractory (“r/r”) acute myeloid leukemia (“AML”), including data from dose escalation and a dose expansion cohort in which patients received lymphodepletion consisting of fludarabine and cyclophosphamide (“Flu/Cy”) prior to NKX101 and from a dose expansion cohort in which patients received modified lymphodepletion consisting of fludarabine and cytarabine (“Flu/Ara-C”) prior to NKX101. The updated clinical data demonstrate that NKX101 was well-tolerated across all dose levels and both lymphodepletion regimens. No dose-limiting toxicities were observed. Myelosuppression and infection, which are common in this patient population following lymphodepletion, were the most common higher-grade adverse events experienced by the thirty patients with r/r AML that received Flu/Cy lymphodepletion, as well as by the six patients that received Flu/Ara-C lymphodepletion. The clinical data also demonstrate that NKX101 had antileukemic activity in patients with r/r AML that received Flu/Ara-C lymphodepletion, the majority of which had high-risk disease. In the dose expansion cohort in which patients received Flu/Ara-C lymphodepletion, a cycle of treatment consisted of Flu/Ara-C lymphodepletion followed by three weekly doses of NKX101 at 1.5 billion cells per dose. Four out of six patients in that dose expansion cohort achieved either a complete response with hematologic recovery (“CR”) or a complete response with residual thrombocytopenia (“CRi”) after receiving at least one cycle of NKX101 (67% CR/CRi rate), and three out of the six patients achieved a complete response with hematologic recovery (50% CR rate). Out of the eighteen patients with r/r AML that received standard lymphodepletion of Flu/Cy and the highest doses of NKX101 (3 weekly doses at 1 billion or 1.5 billion cells per dose) in either a dose escalation or dose expansion cohort, four patients achieved CR/CRi (22% CR/CRi rate) and three achieved a complete response with hematologic recovery (17% CR rate). The expansion cohort incorporating Flu/Ara-C lymphodepletion remains open for enrollment in the NKX101 Phase 1 clinical trial.

Interim data from clinical trials are subject to the risk that one or more of the clinical outcomes may materially change as patient enrollment continues and more data on existing patients become available. The clinical trial program is ongoing, and the final results may be materially different from those reflected in any interim data the Company reports. Further, others, including regulatory agencies, may not accept or agree with the Company’s assumptions, estimates, calculations, conclusions or analyses or may interpret or weigh the importance of data differently, which could impact the value of the particular program, the approvability or commercialization of the particular product candidate or product and the value of the Company in general. In addition, the information the Company chooses to publicly disclose regarding a particular study or clinical trial is typically a summary of extensive information, and others may not agree with what the Company determines is the material or otherwise appropriate information to include in its disclosure, and any information the Company determines not to disclose may ultimately be deemed significant with respect to future decisions, conclusions, views, activities or otherwise regarding a particular product, product candidate or business.