Abstract OT2-21-01: Assessing Response to neoadjuvant Taxotere and TrAstuzumab in Nigerian women with HER2-positive breast cancer (ARETTA)

Abstract

Abstract Background: Populations of African ancestry are underrepresented in global oncology clinical trials resulting in paucity of data on safety and efficacy of cancer medicines in vulnerable Black populations. The ARETTA clinical trial was initiated by the Nigerian Breast Cancer Study Team in partnership with the University of Chicago Comprehensive Cancer Center to build local capacity for biomarker informed clinical trials and translational breast cancer research. ARETTA is a pragmatic single-arm, phase II clinical trial to optimize therapy and determine the safety and efficacy of neoadjuvant taxotere and trastuzumab in women with HER2-positive breast cancer. The study sought to 1) determine the pathological complete response (pCR) rate of patients with early stage breast cancer to neoadjuvant docetaxel and subcutaneous trastusumab 2) develop the capacity of investigators in Nigeria to improve quality of care through participation in oncology clinical trials using upgraded facilities and trained personnel and 3) determine accrual rate and retention of participants. Methods: Inclusion criteria include treatment naïve women aged 18 years to 70 years with HER-2 positive breast cancer stages II-IIIC (AJCC). Eligible participants receive four cycles of docetaxel 75mg/m2 and trastuzumab every 3 weeks. Those with incomplete clinical response by breast ultrasound volume measurements receive 3 additional cycles of chemotherapy; cyclophosphamide 600mg/m2, epirubicin 90mg/m2 and 5-fluorouracil 600mg/m2 every 3 weeks before re-evaluation for surgery. All participants receive a fixed dose of sub-cutaneous Herceptin (600mg) every 3 weeks (total of 18 doses). The primary endpoint is pCR rate. Secondary objectives are to evaluate invasive disease-free survival (iDFS), the pattern of response and mechanisms of resistance to treatment based on genomic markers, the pharmacokinetics of Herceptin SC, quality of life, and adverse event rates, including cardiac toxicity. Planned enrollment is 47 evaluable patients, which will provide 90% power to test the null hypothesis that the pCR rate is 20% versus a 40% alternative (one-sided alpha=0.05). More protocol details can be found at ClinicalTRial.gov NCT03879577 and JCO Glob Oncol2020 doi: 10.1200/GO.20.00043 Progress: The study has met its primary endpoint and will be closed to accrual by the time of the meeting. Results will be submitting as Late Breaking before the meeting Citation Format: Atara Ntekim, Adenike Adeniji-Sofoluwe, Abiola Ibraheem, Anthonia Sowunmi, Ayorinde Folasire, Thomas Olajide, Olalekan Olasehinde, Akinwunmi Komolafe, AbdulRazzak Lawal, Foluso Omodele, Ayodele Sanni, Mustapha Ajani, Olayinka Kotila, Sharifat Folorunsho, Tonyin Aniagwu, Adewumi Alabi, Abiodun Popoola, Chioma Asuzu, Adetola Daramola, Chinedum Babalola, Theodore Karrison, Fatimah Abdulkareem, Olufunmilayo I. Olopade. Assessing Response to neoadjuvant Taxotere and TrAstuzumab in Nigerian women with HER2-positive breast cancer (ARETTA) [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr OT2-21-01.