Trethera Receives FDA Fast Track for Cancer Treatment Combo

LOS ANGELES, Oct. 01, 2026 /CourierPR/ -- Trethera Corporation, a clinical stage biopharmaceutical company developing first-in-class therapies for cancer and autoimmune diseases, has received Fast Track designation from the U.S. Food and Drug Administration (FDA) for its drug TRE-515 in combination with KRAS inhibitors for the treatment of G12C mutation-positive non-small cell lung cancer (NSCLC). This treatment is for patients who have previously received an anti-PD-(L)1 antibody and platinum-based chemotherapy.

Lung cancer remains the leading cause of cancer-related mortality worldwide, with more than 2.5 million new cases and 1.8 million deaths annually. Non-small cell lung cancer (NSCLC) accounts for approximately 80% of lung cancer deaths. The Fast Track designation for TRE-515 in combination with KRAS inhibitors represents an important milestone for the company and further validates its strategy of combining dCK inhibition with targeted cancer therapies.

KRAS inhibitors (KRASi) have significantly transformed the landscape of NSCLC treatment, but response rates remain limited, and many patients experience relapse. The Fast Track designation for lung cancer is a testament to the potential of TRE-515 to address a key metabolic escape pathway used by cancer cells and improve outcomes for patients with this devastating disease.

TRE-515 inhibits deoxycytidine kinase (dCK), the key enzyme in the nucleoside salvage pathway, which can become activated and essential for abnormal cell growth in cancer. The drug has demonstrated favorable safety and antitumor activity in an ongoing first-in-human trial. Preclinical studies have shown that KRASi-treated tumors may increase reliance on the salvage pathway as a metabolic support system under therapeutic stress. In these studies, specialized PET imaging showed persistent dCK activity following KRASi treatment, while subsequent TRE-515 treatment completely blocked tumor dCK activity, providing a visual demonstration of the biological rationale for the drug combination.

The Fast Track designation builds on Trethera’s $2.7 million National Institutes of Health (NIH) grant awarded in 2025 to evaluate TRE-515 with KRASi therapies and marks the second Fast Track designation for the company, following its prior designation in metastatic castration-resistant prostate cancer. Fast Track status is intended to facilitate development and expedite review for drugs addressing serious conditions with unmet medical need, including potential eligibility for more frequent FDA communication, Accelerated Approval, and Priority Review if relevant criteria are met.

Figure 1: Specialized [18F]CFA PET radiotracer showing persistent dCK activity in a tumor-bearing mouse following KRASi treatment (left), followed by complete blockade of tumor dCK activity after TRE-515 treatment (right).

TRE-515 is a first-in-class clinical-stage drug that inhibits deoxycytidine kinase (dCK), the rate-limiting enzyme in the nucleoside salvage pathway, one of two biosynthetic pathways that generate DNA precursors. It is believed that some forms of cancer may be preferentially dependent on the salvage pathway to support tumor growth, and certain autoimmune diseases might also respond to TRE-515 treatment. The FDA has designated TRE-515 a Fast Track drug for prostate and lung cancer and an Orphan Drug for two autoimmune neurologic diseases. Trethera is developing TRE-515 for use as a monotherapy or in combination to precisely target a metabolic vulnerability in cancer and autoimmune diseases, with the goal of transforming outcomes for patients.