MEDSIR's PHERGain Trial Shows Potential for Chemotherapy-free Treatment of HER2-positive Early Breast Cancer
MEDSIR announced today the positive results of the PHERGain trial. This study is the first to use an adaptive design that tailors treatment in the neoadjuvant/adjuvant setting of patients with HER2-positive early breast cancer. The main objective of this trial was to assess the feasibility of a chemotherapy-free strategy based on a dual HER2 blockade with trastuzumab and pertuzumab through a positron emission tomography (PET)-based, pathologic complete response response(pCR)-adapted strategy.
Figure: PHERGain used an adaptive clinical trial design
PHERGain is a randomized, controlled phase 2 clinical trial that involved 356 early-stage HER2-positive breast cancer patients from 45 centers in seven European countries. It was sponsored by MEDSIR, a company dedicated to advancing clinical research in oncology, and led by scientific investigators Dr. Javier Cortés, Dr. Antonio Llombart-Cussac, and Dr. José Pérez. The first primary endpoint was the pCR rate in patients with PET response included in group B, whose positive results were published in 2021 in Lancet Oncology.
The results of the second primary endpoint, 3-year invasive disease-free survival in all patients assigned to group B, have been presented at the 2023 American Society of Clinical Oncology (ASCO) congress. Overall, 95.4% of patients who followed this chemotherapy de-escalation strategy using PHERGain's adaptive design remained cancer-free after three years of follow-up from breast cancer surgery. This is especially relevant because around 30% of these patients did not receive chemotherapy without compromising patient's outcome. Among this latter group, 98.9% remained cancer-free after three years of follow-up from breast cancer surgery.
"This study offers a potential future therapeutic option that enables a significant reduction of toxicity and an improvement in quality of life for this patient population without reducing efficacy", explains Dr. Cortés. In addition, the most relevant finding "is that 99% of the subgroup who received anti-HER2 therapy without chemotherapy have not presented a recurrence of the disease after three years of follow-up".
"These results bring us closer to the end of chemotherapy in a significant percentage of patients with this type of tumor," explains Dr. Llombart-Cussac, "It is critical to design more efficient strategy-based clinical trials with adaptive designs to bring effective therapies to patients in the shortest amount of time."