Our lead therapy in clinical development, larotrectinib, is an oral and selective inhibitor of tropomyosin receptor kinases (TRK), a family of signaling proteins that play an important role in cellular communication and tumor growth.

Growing research suggests that the NTRK genes, which encode for TRKs, can become abnormally fused to other genes, resulting in growth signals that can lead to cancer in many sites of the body. Larotrectinib was purpose-built to directly target TRK, and nothing else, turning off the signaling pathway that allows TRK fusion cancers to grow. We believe that selectively inhibiting TRK is crucial to maximizing the potential for efficacy, while minimizing the risk of off-target toxicities. Larotrectinib is the only selective TRK inhibitor in clinical development.

The FDA has granted larotrectinib the following designations:

  • September 2015: Orphan drug designation for the treatment of solid tumors harboring NTRK-fusion proteins.
  • June 2016: Rare pediatric disease designation for infantile fibrosarcoma
  • July 2016: Breakthrough therapy designation “for the treatment of unresectable or metastatic solid tumors with NTRK-fusion proteins in adult and pediatric patients who require systemic therapy and who have either progressed following prior treatment or who have no acceptable alternative treatments.”
  • May 2018: FDA granted Priority Review for the treatment of adult and pediatric patients with locally advanced or metastatic solid tumors harboring an NTRK gene fusion.

In December 2017, Loxo Oncology initiated submission of a rolling New Drug Application (NDA) for larotrectinib to the U.S. FDA, which was completed in March 2018. In May 2018, the FDA accepted the company’s NDA and granted Priority Review for larotrectinib for the treatment of adult and pediatric patients with locally advanced or metastatic solid tumors harboring an NTRK gene fusion. The FDA has set a target action date of November 26, 2018, under the Prescription Drug User Fee Act (PDUFA).

Larotrectinib was developed through our discovery and development partnership with Array BioPharma.

Larotrectinib Phase 1 Trial

Larotrectinib is currently being evaluated in an ongoing multicenter, open-label, Phase 1 study in adult subjects with advanced solid tumors that have progressed or are non-responsive to available therapies and for which no standard or available curative therapy exists.

Larotrectinib Phase 2 Basket Trial

In October 2015, we began a global, multi-center, single-arm, open-label Phase 2 basket trial in adult patients with solid tumors harboring TRK fusions. As a basket trial, the Phase 2 trial enrolls patients regardless of where their cancer arises in the human body, so long as the cancer harbors a TRK gene fusion.

Larotrectinib Phase 1/2 Pediatric Trial

In December 2015, we began a global, multicenter, open-label Phase 1 trial in pediatric patients with advanced solid or primary CNS tumors. The trial uses a liquid formulation of larotrectinib designed specifically for patients unable to swallow capsules.

For additional information about any of the larotrectinib clinical trials, please refer to www.clinicaltrials.gov or www.loxooncologytrials.com. Interested patients and physicians can contact the Loxo Oncology Physician and Patient Clinical Trial Hotline at 1-855-NTRK-123.

Policy for Access to Investigational Agents

Loxo Oncology is committed to helping patients who have not responded to available therapies and may benefit from its investigational therapies. Loxo Oncology’s Policy for Access to Investigational Agents describes the principles that the company will follow when considering a request, view here.