Study Evaluating the Efficacy of a Double Immunotherapy Combined With Olaparib in Patients With Solid Cancers and Carriers of Homologous Recombination Repair Genes After Olaparib Treatment

Brief summary public domain (ClinicalTrials.gov)

The study propose to generate a clinical trial based on precision medicine to evaluate the use of immunotherapy in patients with altered homologous recombination repair genes and without progression after prior targeted therapy.

Detailed description public domain (ClinicalTrials.gov)

With the development of cost effective and rapid technology of genome sequencing, precision medicine becomes a new way to think oncology. Current targets involve mainly tyrosine kinase, but DNA repair machinery could also be targetable. Some of DNA repair aberrations have been associated with sensitivity to platinum and poly (adenosine diphosphate \[ADP\]-ribose) polymerase (PARP) inhibitors like Olaparib, suggesting that treatment with a PARP inhibitor may exploit a synthetic lethal interaction when the presence of alteration of the homologous repair pathway was observed. PARP is involved in multiple aspects of DNA repair, and the PARP inhibitor Olaparib has recently been approved for treating ovarian cancers with BRCA1/2 mutations. In addition, it showed that using a high-throughput, next-generation sequencing assay in prostate cancer, detection of genomic alteration in genes involved in homologous repair pathway BRCA2, ATM, BRCA1, PALB2, CHEK2, FANCA, and HDAC2, is associated with response to olaparib. Thus demonstrating the clinical validation of the usage of precision medicine to position PARP inhibitor like olaparib in different cancer types based on molecular analysis. Preclinical studies showed DNA damage promotes neoantigen expression. It is possible that increased DNA damage by PARPi would yield greater mutational burden and expand neoantigen expression, leading to greater immune recognition of the tumor. PARPi is also associated with immunomodulation. The PARPi talazoparib increases the number of peritoneal CD8+ T cells and natural killer cells and increases production of interferon (IFN)-γ and tumor necrosis factor-α in a BRCA1-mutated ovarian cancer xenograft model. Hence, addition of PARPi to immune checkpoint blockade could complement the clinical benefit of immune checkpoint inhibition. Such high level of mutation results in high number of neoantigen and antitumor immune response thus given the rational to use immunotherapy to target such type. A recent paper validate this strategy using the anti PD-1 pembrolizumab Some case reports suggest also that other mutations that induce hypermutated tumor (POLD, POLE, or MYH) could gain benefit from anti PD-1 therapy. Additional DNA repair machinery dysfunction may lead to accumulation of mutations. And such level of mutations could induce better response to immunotherapy. In the lung non-small cell setting high mutation rate were associated with better efficacy of both nivolumab and pembrolizumab.