e-Poster Presentation Clinical Oncology Society of Australia Annual Scientific Meeting 2020

Recruitment, outcomes and toxicity trends in phase I oncology trials: six-year experience in a large institution (#299)

Siddharth Menon 1 2 , Amy Davies 1 , Sophia Frentzas 1 3 , Chery-Ann Hawkins 4 , Eva Segelov 1 3 , Daphne Day 1 3 , Ben Markman 3 4
  1. Monash Health, Melbourne, VIC, Australia
  2. Olivia-Newton John Cancer Research Institute, Melbourne, VIC, Australia
  3. Monash University, Melbourne, VIC, Australia
  4. The Alfred Hospital, Melbourne, VIC, Australia

Background: Patterns in oncology phase I clinical trials have changed significantly in recent years due to new classes of therapies, more combination treatments and changing patient demographics. We performed a retrospective review at our institution to examine patient and trial characteristics, screening outcomes and treatment outcomes.

Methods: We analysed all consecutive adult patients with advanced solid organ malignancies who were screened across phase I trials from January 2013 to December 2018 at a single institution.

Results: During this period, 242 patients were assessed for 28 different trials. Median age was 64 years (range 30 – 89) with an equal sex distribution. Amongst 257 screening visits, the overall screen failure rate was 18%, resulting in 212 patients being enrolled onto a study. Twenty-six trials (93%) involved immunotherapeutic agents or molecular targeted agents either alone or in combination, with only two trials of cytotoxic agents (7%). Twenty-two (13.4%) of the 209 treated patients experienced a total of 33 grade 3 or higher treatment-related adverse events. There was one treatment-related death (0.5%). Of 190 response-evaluable patients, 7 (4%) had a complete response, 34 (18%) a partial response and 59 (31%) experienced stable disease for a disease control rate of 53%. The overall response rate for immuno-oncology (IO) trials was superior to non-IO trials (28% vs. 14%,  p = 0.022). Furthermore, combination trials yielded a superior ORR than single-agent studies (33% vs. 16%; p = 0.005) The median overall survival for our cohort was 8.0 (95% CI 6.8 – 9.2) months.

Conclusion: The profile of phase I trials at our institution are consistent with the changing early drug development landscape. Response rates and overall survival in our cohort are superior to historically reported rates and comparable to contemporaneous studies. Severe treatment-related toxicity was relatively uncommon, and treatment-related mortality was rare.

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  3. Chakiba C, Grellety T, Bellera C, Italiano A. Encouraging Trends in Modern Phase 1 Oncology Trials. New England Journal of Medicine. 2018;378(23):2242-2243.