4536 - Safety and preliminary clinical activity of repotrectinib in patients with advanced ROS1/TRK fusion-positive solid tumors (TRIDENT-1 study)

Background

Repotrectinib is a next-generation ROS1/TRK/ALK TKI with >90-fold potency versus crizotinib against ROS1 and >100-fold potency versus larotrectinib against TRK in engineered Ba/F3 cell proliferation assays. Preclinical studies demonstrate robust activity against all known ROS1/TRK resistance mutations, including the most common solvent-front mutations (SFM) ROS1 G2032R, TRKA G595R, and TRKC G623R/E.

Methods

In the ongoing phase 1 study (NCT03093116), TKI-naïve and TKI-pretreated (≥1 TKI) pts with advanced ROS1, TRK, or ALK fusion+ solid tumors received repotrectinib. Endpoints include safety, PK, and confirmed overall response (cORR).

Results

As of 4-March-2019, 83 pts were treated with repotrectinib (dose levels from 40 mg QD to 200 mg BID under fasted/fed conditions). Most AEs were manageable and grade (gr) 1-2. The most common treatment-emergent AEs (found in > 30% of pts) were dizziness (57%), dysgeusia (51%), dyspnea (30%), and fatigue (30%). Four DLTs occurred and were manageable with dose modifications: gr3 dyspnea/hypoxia (n = 1); gr2 (n = 1) and gr3 (n = 1) dizziness at 160 mg BID, and gr3 dizziness (n = 1) at 240 mg QD. In ROS1+ NSCLC, the median number of prior TKIs was 1 (0-3); all TKI-naïve and 77% of TKI-pretreated pts received prior chemotherapy. In 11 evaluable TKI-naïve ROS1+ NSCLC pts, cORR by Blinded Central Review (BCR) was 82% (95% CI 48 - 98); median duration of response was not reached ((range 5.6 - 17.7+ months (mos)). In 18 ROS1+ NSCLC pts pretreated with 1 prior TKI, cORR by BCR was 39% (95% CI 17 – 64), and in 11 pts with 1 prior TKI at doses of 160 mg QD or above cORR was 55% (95% CI 23 - 83). All pts with ROS1 G2032R had tumor regression [cORR of 40% (n = 2/5)]. In 1 TKI-pretreated pt with ETV6-NTRK3+ and an acquired TRKC G623E-mutant salivary gland tumor, a cPR of 9.8 mos was achieved; the patient was treated for 17.9 mos. Enrollment continues. Updated data in ∼10 additional ROS1+ NSCLC and TRK+ solid tumor pts will be presented.

Conclusions

Repotrectinib was well tolerated and demonstrated encouraging overall clinical activity in pts with ROS1 fusion-positive NSCLC and TRK fusion-positive solid tumors.

Clinical trial identification

NCT03093116.

Editorial acknowledgement

Legal entity responsible for the study

Turning Point Therapeutics Inc, San Diego, CA, USA.

Funding

Turning Point Therapeutics Inc, San Diego, CA, USA.

Disclosure

A. Drilon: Honoraria (self), Advisory / Consultancy: Ignyta/Genentech/Roche; Honoraria (self), Advisory / Consultancy: Loxo Oncology/Bayer/Lilly; Honoraria (self), Advisory / Consultancy: TP Therapeutics Inc; Honoraria (self), Advisory / Consultancy: AstraZeneca; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): Pfizer; Honoraria (self), Advisory / Consultancy: Blueprint Medicines; Honoraria (institution), Advisory / Consultancy: Takeda/Ariad/Milenium; Honoraria (self), Advisory / Consultancy: Helsinn; Honoraria (institution), Advisory / Consultancy: Beigene; Honoraria (self), Advisory / Consultancy: BergenBio; Honoraria (self), Advisory / Consultancy: Hengrui Therapeutics; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): Exelixis; Honoraria (self), Advisory / Consultancy: Tyra Biosciences; Research grant / Funding (institution): Foundation Medicine; Licensing / Royalties: Wolters Kluwer; Travel / Accommodation / Expenses: Merck; Honoraria (self), Advisory / Consultancy: MORE Health; Honoraria (self), Advisory / Consultancy: Verastem; Travel / Accommodation / Expenses: Puma; Research grant / Funding (institution): Teva; Research grant / Funding (institution): GlaxoSmithKlein. B.C. Cho: Shareholder / Stockholder / Stock options: heraCanVac Inc; Honoraria (self), Speaker Bureau / Expert testimony, Research grant / Funding (self): Novartis; Honoraria (self), Research grant / Funding (self): Bayer; Honoraria (self), Research grant / Funding (institution): AtraZeneca; Honoraria (self), Research grant / Funding (institution): MOGAM Institute; Honoraria (self): Dong-A ST; Licensing / Royalties: Champions Oncology. J.J. Lin: Speaker Bureau / Expert testimony: TP Therapeutics Inc; Honoraria (institution): Chugai; Honoraria (institution): Boehringer-Ingelheim. V. Zhu: Shareholder / Stockholder / Stock options: TP Therapeutics Inc; Honoraria (self), Speaker Bureau / Expert testimony, Travel / Accommodation / Expenses: Astra Zeneka; Honoraria (institution), Speaker Bureau / Expert testimony, Travel / Accommodation / Expenses: Takeda; Honoraria (self): Biocept; Speaker Bureau / Expert testimony, Travel / Accommodation / Expenses: Roche/Genentech. R.D. Camidge: Research grant / Funding (self): Takeda. S. Stopatschinskaja: Travel / Accommodation / Expenses, Shareholder / Stockholder / Stock options, Full / Part-time employment: TP Therapeutics Inc. J..J. Cui: Leadership role, Travel / Accommodation / Expenses, Shareholder / Stockholder / Stock options, Full / Part-time employment: TP Therapeutics Inc. D.M. Hyman: Advisory / Consultancy, Travel / Accommodation / Expenses: Chugai; Advisory / Consultancy: CytomX Therapeutics; Advisory / Consultancy: Boehringer Ingelheim; Advisory / Consultancy, Research grant / Funding (self): AstraZeneca; Advisory / Consultancy: Pfizer; Advisory / Consultancy, Research grant / Funding (self): Bayer; Advisory / Consultancy, Travel / Accommodation / Expenses: Genentech; Research grant / Funding (self): Puma Biotechnology; Research grant / Funding (self): Loxo. S. Ou: Advisory / Consultancy, Research grant / Funding (institution), Shareholder / Stockholder / Stock options: TP Therapeutics Inc; Shareholder / Stockholder / Stock options: Ignyta; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): Pfizer; Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony, Research grant / Funding (institution): AstraZeneca; Honoraria (self), Advisory / Consultancy, Speaker Bureau / Expert testimony, Research grant / Funding (institution): Ariad; Honoraria (institution), Advisory / Consultancy, Speaker Bureau / Expert testimony: Genentech/Roche; Honoraria (self), Research grant / Funding (institution): Ignyta; Honoraria (self): Novartis; Research grant / Funding (institution): Blueprint Medicine. A.T. Shaw: Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): Pfizer; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): Novartis; Honoraria (self), Advisory / Consultancy, Research grant / Funding (institution): Roche/Genentech; Honoraria (self): Foundation Medicine; Honoraria (self): Guardant Health; Advisory / Consultancy, Research grant / Funding (institution): Ariad; Advisory / Consultancy, Research grant / Funding (institution): Ignyta; Advisory / Consultancy: Blueprint Medicine; Advisory / Consultancy, Research grant / Funding (institution): Daiichi Sankyo; Advisory / Consultancy: EDM Serono; Advisory / Consultancy: Taiho Pharmaceutical; Advisory / Consultancy: KSQ Therapeutics; Advisory / Consultancy: Natera; Advisory / Consultancy: Loxo; Advisory / Consultancy: Takeda; Advisory / Consultancy: Bayer; Advisory / Consultancy: Chugai Pharm; Research grant / Funding (institution): TP Therapeutics. R.C. Doebele: Speaker Bureau / Expert testimony: Takeda; Advisory / Consultancy, Licensing / Royalties: Ignyta; Speaker Bureau / Expert testimony: AstraZeneca; Advisory / Consultancy: Bayer; Advisory / Consultancy: Genentech; Shareholder / Stockholder / Stock options: Roche; Research grant / Funding (institution), Licensing / Royalties: Rain Therapeutics; Licensing / Royalties: Abbott Molecular. All other authors have declared no conflicts of interest.