eFFECTOR’s Tomivosertib Demonstrates Positive Phase 2 Results for Subjects with Non-Small Cell Lung Cancer in Combination with Checkpoint Inhibitors

Addition of Tomivosertib Conferred Benefit in Subjects Progressing on Checkpoint Inhibitors Alone

Data presented at the American Society for Clinical Oncology 2020 Virtual Scientific Program

SAN DIEGO, MAY 29, 2020 – eFFECTOR Therapeutics, Inc., a leader in the development of selective translation regulation inhibitors (STRIs) for the treatment of cancer, today announced that positive Phase 2 data from its pipeline program tomivosertib (eFT508), will be presented at the ASCO 2020 Virtual Scientific Program at 8:00 a.m. ET on May 29. The data demonstrates tomivosertib’s potential as a therapeutic solution for common resistance mechanisms to checkpoint inhibitors.

In a Phase 2 study, open-label study, tomivosertib demonstrated antitumor activity in combination with check point inhibitors (CPI) in patients with solid tumors who progressed on CPI treatment. In the study, 41% of patients with non-small cell lung cancer treated with tomivosertib showed progression free survival at 24 weeks. The median progression free survival rate was 19 weeks, and all NSCLC subjects entered the study with progression by RECIST 1.1 on single agent checkpoint inhibitor prior to adding tomivosertib.

“Tomivosertib was designed to down regulate multiple immunosuppressive factors by acting at the level of mRNA translation and our clinical data continue to highlight the potential of tomivosertib to complement focused immune checkpoint inhibitor activity such as anti-PD-1 and PD-L1 agents,” said Steve Worland, Ph.D., president and chief executive officer of eFFECTOR. “This study underscores the importance of progression free survival for patients who may experience extended and improved quality of life on checkpoint inhibitors with the addition of tomivosertib prior to switching to cytotoxic salvage therapy.”

Secondary objectives for the current study include characterizing the pharmacokinetics and safety of tomivosertib when added to an anti-PD-1/anti PD-L1 therapy. There were no grade 5 treatment-emergent adverse events (TEAEs) related to tomivosertib and the majority of TEAEs were grade 1 or 2.

About Tomivosertib (eFT508)
Tomivosertib is eFFECTOR’s wholly-owned, highly selective translation regulation inhibitor that targets MNK1 and MNK2 (MNK1/2) acting at the level of mRNA translation. The oral small molecule drug candidate promotes anti-tumor immune activity by selective down regulation of several immune checkpoint receptors and specific immunosuppressive cytokines. Tomivosertib is being evaluated as an add-on when patients are experiencing insufficient response to an FDA-approved checkpoint inhibitor [NCT03616834].It is also under evaluation in advanced breast cancer in combination with paclitaxel as part of a study led by researchers at McGill University and fully funded by Stand Up to Cancer Canada.

Please visit www.clinicaltrials.gov for further information on ongoing clinical studies of tomivosertib.

eFFECTOR is a next-generation oncology company developing a new class of targeted therapies called selective translation regulator inhibitors (STRIs) that restore control of the processes that cancer cells manipulate for survival. The company’s pipeline of product candidates target the cellular translation machinery that drive different, complementary systems cancer harnesses for growth and proliferation, creating the potential for combination use with each other or existing therapeutics. Tomivosertib, an inhibitor of MNK 1/2, works at multiple points in the cancer immunity cycle, and has demonstrated efficacy in a Phase 2 clinical trial in patients who progressed on checkpoint inhibitors. Zotatifin targets eIF4A, an enzyme responsible for unwinding complex RNA structures to facilitate transcription initiation. In preclinical studies, Zotatifin demonstrated broad activity against multiple types of KRAS mutant and receptor tyrosine kinase mutant tumors, and is being evaluated in an ongoing Phase 1 study in patients with solid tumors.


Amy Conrad
Juniper Point

Heidi Chokeir, Ph.D.
Canale Communications