Gritstone Unveils "Off-The-Shelf" Neoantigen Immunotherapy Data In Lung Cancer

Gritstone bio Inc GRTS has announced results with its SLATE v1 product ("off-the-shelf" shared neoantigen immunotherapy).
The therapy is in combination with Bristol-Myers Squibb Co's BMY intravenous Opdivo (nivolumab) and subcutaneous Yervoy (ipilimumab). The Company has also dosed the first patient in Phase 2 trial of the optimized SLATE v2 product.
SLATE v2 has been engineered to drive a more potent immune response to mutant KRAS neoantigens than were observed with SLATE v1.
SLATE v1 exhibited efficacy in patients with NSCLC who had all progressed on prior anti-PD-(L)1 therapy with molecular responses observed in 3/5 NSCLC patients who were eligible for analysis.
Among 6 NSCLC patients, ctDNA responses were observed in 66% of these patients (2/3 eligible for analysis). An unconfirmed radiologic response was observed in one 2nd line patient who had progressed after three months of 1st line chemo-immunotherapy.
One patient who had progressed on prior chemo-immunotherapy after eight months of treatment is nearing completion of 2 years of therapy with persistent ~20% tumor lesion shrinkage. The patient's ctDNA was undetectable throughout the study.
The SLATE v2 Phase 2 portion of the study will enroll up to 60 patients with KRAS mutant-driven tumors in total across three cohorts.
Price Action: GRTS shares are up 3.69% at $14.04 during the premarket session on the last check Friday.