Vall d'Hebron Institute of Oncology (VHIO) guided study hails a new horizon in the battle against cancer, opening up a parallel dimension to treatment choices already available. The data, published today in the Journal of Clinical Oncology, demonstrate that by combining two drugs that had already been used on a patient in the past but had stopped working, they boost each other's efficacy and at the same time manage to break down the patient's resistance to each of them individually, presenting a third potential treatment option for clinically advanced metastatic tumours.
While this may not initially appear to be an innovation, given that combined treatments are used in cancer as a matter of course, it actually represents a radical change in the use of the existing therapeutic weaponry, an extremely practical solution and a source of hope for many patients. "The novelty factor does not lie in the combination itself, but in the combination of two drugs that had already been administered in the past and had each failed", explained Dr Javier Cortés, the Head of the Breast Cancer Programme at the VHIO and main author of this work. This not only offers new alternatives for patients with advanced tumours -the most important aspect - but also opens up a parallel dimension of new therapeutic options to the existing treatments, given that it offers numerous combinations between existing pharmacological treatments that not only boost each other but also counteract patients' resistance to them. "The study focused on HER2 positive breast cancer, although the concept could be applied to the treatment of other tumours", continued Dr Cortés.
In the fight against cancer, the combination of treatments is highly common practice. However, the concept described is different: it is not about seeing the results of combining drug A with drug B, but, when A fails to work, B is administered, and if this also fails we return to the starting point and initiate treatment with a combination of the two (A + B). This strategy could offer an unprecedented key to multiplying treatment options.
In the specific case of this study, we administered trastuzumab (the first-choice treatment for HER2 positive breast cancer); when the tumour continued growing we used pertuzumab (currently pending approval) and when the cancer continued to progress we administered the two together. "The results were very positive and highly informative for new studies", said Dr Cortés.