Two new cancer drugs used in combination have been shown to be more effective than chemotherapy on its own, in a recent study carried out at a range of institutions in the US.
The first, bevacizumab, is a drug targeted as an antibody to negate a signalling protein which often causes cancerous growth. This was used in combination with a second drug, erlotinib, which works as a kinase inhibitor, targeting a different signalling protein again known to encourage cancerous growth. The combination had demonstrated encouraging results in phase I trials and has recently finished phase II trials with good results and limited side effects:
The study, published in October’s Journal of Clinical Oncology, tested the safety of combining bevacizumab, already an established targeted drug for non small cell lung cancer (NSCLC), with either chemotherapy or the new drug erlotinib. At the same time it compared these combinations with standard chemotherapy on its own. Success was measured by noting the length of the patient’s progression free survival (PFS); the time before tumour develops further.
All of the 120 patients studied had NSCLC that had got worse during or after standard chemotherapy previously carried out.
The proportion of patients that survived at least one year without the worsening of their tumour was found to be 57.4% for the bevacizumab and erlotinib combined treatment. This was better than either of the other options: Chemotherapy combined with bevacizumab resulted in 53.8% PFS and chemotherapy alone 33.1% PFS.
This result is unusual in that it is the first time two targeted agents have been shown to be more effective in combination than chemotherapy, either alongside their use or on its own. This is especially important as these targeted agents are less toxic than the standard chemotherapy, and so far have given less detrimental side effects.