Minority participation in phase 1 gynecologic oncology clinical trials: Three decades of inequity

Objectives: It is important to develop effective therapies in minorities to ensure equity in cancer care. Underrepresentation of minorities in early phase trials may cause therapies that are effective only in majority populations. We evaluated minority participation in gynecologic oncology phase 1 clinical trials.

Methods: In peer-reviewed published articles of gynecologic oncology phase 1 clinical trials from years 1985 to 2018, we manually abstracted racial distribution of enrolled participants, cancer type, and year published. We calculated expected and observed ratios of racial participation on the basis of age-adjusted cancer incidence for race from the United States Centers for Disease Control and Prevention.

Results: We identified 357 articles of phase 1 trials (total, 9492 participants), including 213 articles on ovarian cancer (60%). Racial distribution of participants was available in 84 articles (23%) that included 2483 participants (26%): 1950 white (79%), 140 black (5%), and 393 other participants (16%). Other nonwhite races exceeded black enrollment in 46 of 84 trials (55%) that listed race. Enrollment of black participants was less than expected from disease incidence for ovarian (incidence-to-enrollment ratio, 18.5; P < .001), endometrial (3.6; P < .001), and cervical cancer (6.8; P < .001). No phase 1 study met expected enrollment for black participants. Frequency of black participants decreased 1.8-fold from 1995 to 1999 (8 of 70 participants [11%]) to 2015-2018 (55 of 892 participants [6%]; P < .025).

Conclusions: Major racial underrepresentation exists in gynecologic oncology phase 1 clinical trials. Enrollment of more black participants is needed to achieve racial equity.