Purple Biotech’s IM1240 Shows 100% Response Across Seven Resistant Tumor Samples
Purple Biotech’s lead candidate IM1240 elicited anti-tumor responses in all seven patient-derived, treatment-resistant tumor samples, including PD-1 and chemo-resistant head and neck and bladder cancers. IM1240’s NKG2A arm boosted efficacy and induced tertiary lymphoid structures, CD8 T-cell and NK-cell infiltration while reducing Tregs in NSCLC explants.
1. Preclinical Efficacy Results
IM1240 demonstrated potent anti-tumor activity across all seven patient-derived tumor samples tested, which included PD-1 or PD-1/chemo-resistant head and neck squamous cell carcinoma metastatic lymph nodes and enfortumab vedotin plus PD-1-resistant muscle-invasive bladder cancer specimens.
2. NKG2A Arm Contribution
The NKG2A arm of IM1240 significantly enhanced apoptotic activity, as shown by loss of efficacy in a variant with a mutated NKG2A-binding domain, confirming its critical role in boosting anti-tumor responses across all samples.
3. Immune Remodeling in NSCLC Explants
Treatment of patient-derived non-small cell lung cancer biopsies with IM1240 induced mature tertiary lymphoid structures, increased CD8 T-cell and NK-cell abundances, and reduced regulatory T-cell and tumor cell numbers, correlating with observed anti-tumor efficacy.
4. Platform and Development Outlook
Purple Biotech’s CAPTN-3 platform employs masked tri-specific antibodies to engage CD3, tumor antigens, and NKG2A within the tumor microenvironment, with IM1240 advancing toward clinical evaluation and a second candidate, IM1305, in preclinical development, highlighting a broad potential market opportunity.