Shares of Akari Therapeutics PLC (NASDAQ:AKTX) jumped roughly 50% in after-hours trading on Thursday after the company disclosed preclinical data indicating synergistic activity of its lead antibody drug conjugate, AKTX-101, when combined with KRAS inhibitors in pancreatic cancer models.
The data were released in an abstract tied to the American Society of Clinical Oncology Annual Meeting 2026. According to Akari, AKTX-101 paired with adagrasib produced synergistic cell killing in pancreatic cancer cell lines that harbor KRAS G12D and KRAS G12C mutations. By contrast, first-in-class topoisomerase I-targeting TROP2 ADCs did not show the same synergy with adagrasib and instead demonstrated antagonistic activity in the same combination tests.
AKTX-101 is described by the company as a TROP2-directed ADC that leverages Akari’s proprietary PH1 payload, which modulates the RNA spliceosome. The company attributes the observed synergy to PH1’s mechanism of action - targeting pre-mRNA transcripts for degradation, including transcripts that contain KRAS mutations implicated in driving the cancer models examined.
In its summary of the findings, Akari said the results support the potential for RNA splicing-targeted approaches to have broader applicability in KRAS-driven cancers and help distinguish AKTX-101 from TROP2 ADCs that employ Topoisomerase I inhibitor payloads.
The company has initiated IND-enabling studies for AKTX-101 and reiterated its target of starting a Phase 1 first-in-human clinical trial by mid-2027. Akari also noted that these new data build on results it previously reported at AACR 2026, where AKTX-101 displayed differentiated cytotoxicity and greater potency versus current TROP2 ADCs across multiple tumor models, including bladder, lung and breast cancers.
While the announcement prompted a sharp market reaction, the evidence remains preclinical and focused on cell-line models. Akari’s stated development timeline points to key upcoming regulatory and clinical catalysts - the completion of IND-enabling studies and initiation of a Phase 1 study - both of which will be material to validating the translational relevance of the current results.
Investors and industry observers will likely track subsequent disclosures and the progress of IND-enabling work to assess whether the preclinical synergy translates into a viable clinical combination strategy for KRAS-mutant tumors.