Voice of cancer patients: Patients' experience and concerns regarding CDK 4/6 inhibitors in treatment of breast cancer

Addition of a CDK 4/6 inhibitor to endocrine therapy has demonstrated improved clinical outcomes and delayed the onset of tumor progression in patients with metastatic hormone receptor positive (HR+) breast cancer. The following three CDK 4/6 inhibitors have been approved and are widely used in combination with endocrine therapy: Palbocilib (Palbo) approved in February 2015, Ribocilib (Ribo) in March 2017 and Abemacilib (Abema) in September 2017. In this study we analyzed patients’ use, experiences and concerns regarding these drugs. Method: We collected 18.2 million messages from 53 different unrestricted cancer forums, including 5.8 million messages from 26 breast cancer related forums, which provided clinically relevant information to our platform called “Voice of Cancer Patients (VoCP)”. We created custom ontology regarding breast cancer, its treatment and side effects and then analyzed these messages by using artificial intelligence techniques, e.g., natural language processing and machine learning. Results: • We found 28,231 messages related to CDK 4/6 inhibitors from 3,715 users. 2,731 users shared 15,585 messages regarding their experience with use of these drugs. • Sites of metastasis mentioned: Bones: 884 users, Liver: 352, Lungs: 206, Lymph nodes: 68, Skin: 36 Drugs used with CDK 4/6 inhibitors Percentage of users mentioning side effects: • Fatigue was mentioned by 31.9% users of Palbo, 13% of Ribo and 8% of Abema • Nausea v 60 continued with Fulvestrant and 60 with aromatase inhibitor. • After progression, 70 users mentioned switching to Capecitabine, 33 mentioned switching to Everolimus+Exemestane, 38 users mentioned switching to Fulvetrant+Everolimus and 110 users mention switching various other IV chemotherapies. • 14 patients mentioned switching from Palbo to Ribo and 41 to Abema. • 5 patients switched from Ribo to Palbo and 1 to Abema. • 4 patients switched from Abemo to Palbo and 1 to Ribo. • 60 patients using Palbo mentioned issues with out of pocket cost and 30 patients with insurance. No such mentions were given by the users of Ribo and Abema. Conclusions: All 3 CDK 4/6 inhibitors show similar efficacy. Palbo and Ribo are used more in the first line metastatic treatment whereas Abema in later lines. They have slightly different side effects, e.g., Abema causes less neutropenia and more diarrhea. VoCP provides reliable insights into patients’ point of view about their disease and their treatment and highlights the areas of unmet needs where research and resources should be focused. Citation Format: Sangeeta Aggarwal, Guroosh Chaudhary, Manish Singh, Ankit Gupta, Juhi Jha, Rahul K Gond, Sujeet Kumar, Alok Aggarwal. Voice of cancer patients: Patients’ experience and concerns regarding CDK 4/6 inhibitors in treatment of breast cancer [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P5-11-09.