Abstract 6438: Unfinished stories: Consequences of melanoma clinical trial discontinuation and non-publication

Abstract Background: Melanoma is a major cause of skin cancer-related death, and clinical trials are essential for advancing melanoma treatment options. However, many trials either are terminated prematurely or are never published, eaving critical data unreported. These “unfinished stories”, hinder scientific progress, waste resources, and limit informed clinical decision-making. Therefore, understanding how many and what factors predict unpublished or discontinued melanoma trials is key to improving the transparency of research and advancing best care for patients. Objective: To identify the extent, characteristics, and variables related to Discontinuation and Non-Publication melanoma clinical investigations. Methods: We systematically searched ClinicalTrials.gov for Melanoma studies up to March 1, 2025. Studies completed within the past 24 months were excluded to account for potential delays in the peer review process. Publication status was identified using NCT numbers. Data on participant gender, age, study design, funding source, type of intervention, sample size, and trial location were collected and analyzed. Multiple logistic regression was used to identify factors associated with trial discontinuation or non-publication. All statistical analyses were conducted using Jamovi version 2.6.24. Results: In total, there were 2,144 trials, with 712 (33.2%) published, 1,215 (56.7%) non-published, and 217 (10.1%) unknown. Of the discontinued trials (516, 24.1%), just 59 (11.4%) were published. Non-publication status was noted to be significant among trials of genetic interventions (OR = 0.104, 95% CI: 0.027-0.401, p=0.001), procedural interventions (OR = 0.262, 95% CI: 0.121-0.567, p0.001), and in a multicenter trial (OR = 0.185, 95% CI: 0.123-0.278, p0.001). Also, a study was considerably more probable to be discontinuation if smaller-sized (≤500 participants, p0.001) or earlier (Phase 1/2, p0.001). Conclusions: The high frequency of Discontinuation and Non-Publication trials record highlights the importance of efforts toward completing and/or fully publication melanoma clinical investigations, particularly those for genetic and/or procedural treatments and/or smaller trials. Citation Format: Hadeer Hafez, Abdelrahman Hagag, Mohamed Ashraf Mohamed, Mohamed Saad Rakab, Ismail Zakaria Ismail, Aya Jamal Elkenani, Nada Elmetwally Ahmed, Abdelrahman M. Hafez, Doaa Mashaly, Ali Tarek Lasheen, Mohamed Abdelsalam. Unfinished stories: Consequences of melanoma clinical trial discontinuation and non-publication abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 6438.