Cancer Immunotherapy Studies Report Positive Results 

Gritstone Oncology GRANITE and SLATE are both personalized neoantigen-based immunotherapies

dart board with darts on it around the bulls eye

A California based biotechnology company announced positive findings from a phase 1 study in an oral session at the European Society for Medical Oncology Immuno-Oncology Congress on December 12, 2019.

Gritstone Oncology, Inc. presented preliminary Phase 1 GRANITE immunogenicity data demonstrating the rapid, robust and consistent induction of large numbers of CD8+ T cells against multiple neoantigens in 4 solid tumor patients with available IFN-g ELISpot data (up to 3,000 IFN-g spot forming units per 106 PBMCs were generated, as measured by overnight ELISpot) within the first two dosing cohorts. Importantly, these T cells were also able to produce IL-2 and Granzyme B, demonstrating that they have cytotoxic potential. 

In addition to priming naive CD8+ T cells against encoded neoantigens, the data demonstrate that GRANITE can also stimulate the expansion of pre-existing T-cell populations. 

Safety data from five patients receiving GRANITE and three patients receiving SLATE across the first two dose levels indicate that the immunotherapies were well-tolerated with no dose-limiting toxicities observed. Dose escalation continues. 

“We are thrilled to observe very robust, polyfunctional CD8+ T cells against predicted neoantigens even at the first dose level of our phase 1 study,” said Andrew Allen, M.D., Ph.D., co-founder, president and chief executive officer of Gritstone Oncology, in a related press release.

“We view these preliminary results as important de-risking data, demonstrating the unprecedented immunogenicity of our heterologous prime/boost vaccine platform at its lowest dose, in combination with nivolumab.”

“Pre-clinical data have shown a clear dose-response where higher doses of the self-amplifying RNA boost vaccination, as well as the addition of anti-CTLA-4, further increasing the number and function of CD8+ T cells.”

“Notably, the starting dose of self-amplifying RNA was conservative since this is the first-in-human study with this therapeutic approach.” 

“Therefore, we look forward to presenting mature data at higher doses with additional patients receiving the full immunotherapy regimen in several months.”

Sponsored Links:

In the GRANITE Phase 1 GO-004 study, the first dosing cohort consisted of three advanced cancer patients, including two gastroesophageal adenocarcinoma patients and one non-small cell lung cancer patient who had previously progressed on prior anti-PD-L1 therapy. 

From the second GRANITE dosing cohort, early ELISpot data was available from one microsatellite-stable colorectal cancer patient. 

The most common adverse events in the GO-004 study were grade 1/2 fever and skin rash, consistent with an inflammatory immune reaction. 

In the SLATE Phase 1 GO-005 study, patients are still early in their course of treatment, and treatment-related adverse events have been limited to one injection site reaction and one case of grade 1/2 pruritus.

Gritstone’s GRANITE personalized immunotherapy delivers a cassette of 20 TSNA identified by the company using its proprietary Gritstone EDGE™ artificial intelligence platform and tumor HLA peptide sequencing, representing tumor-specific neoantigens that are derived from the patient’s own tumor. 

GRANITE is being evaluated in combination with immune checkpoint blockade in a Phase 1/2 clinical study, referred to as GO-004, for the treatment of patients with advanced solid tumors, including microsatellite-stable colorectal cancer (MSS CRC), gastroesophageal cancer, metastatic non-small cell lung cancer, and bladder cancer. 

Gritstone Oncology is a clinical-stage biotechnology company, is developing the next generation of cancer immunotherapies to fight multiple cancer types.

Cancer Immunotherapy news published by Vax-Before-Cancer