On January 29, 2021 Turning Point Therapeutics, Inc. (NASDAQ: TPTX), a precision oncology company developing next-generation therapies that target genetic drivers of cancer, reported that updated interim findings from the ongoing TRIDENT-1 registrational study of lead drug candidate repotrectinib in patients with ROS1-positive TKI-naïve non-small cell lung cancer (NSCLC) (Press release, Turning Point Therapeutics, JAN 29, 2021, View Source [SID1234574421]).

Schedule your 30 min Free 1stOncology Demo!
Discover why more than 1,500 members use 1stOncology™ to excel in:

Early/Late Stage Pipeline Development - Target Scouting - Clinical Biomarkers - Indication Selection & Expansion - BD&L Contacts - Conference Reports - Combinatorial Drug Settings - Companion Diagnostics - Drug Repositioning - First-in-class Analysis - Competitive Analysis - Deals & Licensing

                  Schedule Your 30 min Free Demo!

In a total of 15 patients enrolled in the Phase 2 portion of the TRIDENT-1 study, the preliminary efficacy analysis showed the confirmed objective response rate (ORR) by physician assessment was 93% (95% CI: 68-100) and in 22 patients pooled from the Phase 1 (dosed at or above the Phase 2 dose) and Phase 2 portions, the confirmed ORR was 91% (95% CI: 71-99).

The findings will be presented in a mini-oral presentation by Dr. Byoung Chul Cho, Division of Medical Oncology, Yonsei Cancer Center at Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea, at the International Association for the Study of Lung Cancer 2020 World Conference on Lung Cancer.

"These interim data confirm our belief that repotrectinib has the potential to be the best-in-class treatment for patients with ROS1-positive TKI-naïve advanced non-small cell lung cancer," said Mohammad Hirmand, M.D., chief medical officer. "To date, we have enrolled approximately 40 ROS1-positive TKI-naïve patients in the Phase 1 and 2 portions of the TRIDENT-1 study dosed at or above the Phase 2 dose– an encouraging increase in enrollment following our data update from last August—and we look forward to discussing next steps towards registration of repotrectinib in this patient population at a Type B meeting with the FDA anticipated in the first half of the year."

Interim Update
Utilizing a Dec. 31, 2020 cutoff date, the TRIDENT-1 preliminary interim efficacy update includes 22 ROS1-positive TKI-naïve NSCLC patients pooled from the Phase 1 portion of the study (dosed at or above the Phase 2 dose) with patients from the Phase 2 portion who had at least two post-baseline scans. Responses for patients in the Phase 2 portion of the study were determined by physician assessment. The interim safety update includes a total of 185 patients from the Phase 1 and Phase 2 portions of the study utilizing an Oct. 30, 2020 cutoff date.

14 of 15 patients treated in the Phase 2 portion achieved a confirmed ORR of 93% (95% CI: 68-100). At the time of the data cut-off, the one non-responder remained on treatment and in stable disease with a 13% tumor reduction. In addition, one of the 14 patients in a partial response at the time of the data cutoff date has since achieved a confirmed complete response.

Duration of response ranged from 1.3+ to 7.4+ months, and the duration of treatment ranged from 3.7+ to 10.9+ months with 14 of the 15 patients remaining on treatment. As of the cutoff date, one additional patient (not included in the confirmed ORR calculation) had an unconfirmed partial response and was on treatment awaiting a confirmatory scan. The company’s prior Phase 2 update with the data cutoff date of July 10, 2020 in 7 total patients, showed a confirmed ORR of 86% and a wider 95% confidence interval of 42 to 100.

20 of 22 patients pooled from Phase 1 and Phase 2 achieved a confirmed ORR of 91% (95% CI: 71-99). In the 7 patients from the Phase 1 portion dosed at or above the Phase 2 dose, duration of treatment ranged from 10.9 to 37.3 months with a median of 30.9 months, with four patients receiving treatment for longer than 30 months.

Repotrectinib was generally well tolerated in 185 patients treated in the Phase 1 and Phase 2 portions of the study.

Treatment-emergent adverse events (TEAE) found in greater than 15 percent of patients were dizziness (58%), dysgeusia (43%), constipation (32%), dyspnea (31%), fatigue (27%), paresthesia (25%), anemia (22%), nausea (20%), and muscular weakness (16%).

There were four cases of Grade 3 dizziness (2%) and no cases of dizziness have led to treatment discontinuation. Dose modifications due to TEAEs were infrequent, including 18% that led to dose reduction and 9% that led to drug discontinuation.

The majority of treatment related AEs (TRAEs) were Grade 1 or 2 and there were no Grade 4 or Grade 5 TRAEs.