It’s coincidental that after spending so many years leading a few small, oncology-focused biotechnology companies developing immunotherapies, radiopharmaceutical agents, and supportive care oncology products, I am now utilizing that experience, knowledge and network to make informed treatment decisions following my cancer diagnosis. Like driving down a familiar road, I am constantly seeing landmarks and signs that I know quite well from my time in the industry.
For example, some of the common side effects from chemotherapy and radiation therapy include oral mucositis (painful ulcers in the mucosa) and xerostomia (dry mouth). I studied these two side effects extensively as part of the due diligence process when I licensed and launched an advanced electrolyte solution called Caphosol® back in 2006. Based on this experience, I know what to expect from my chemoradiation treatment and hope to incorporate Caphosol into my arsenal against these debilitating side effects.
While the streets may be familiar at times, I am still faced with difficult decisions at some of the crossroads. The latest example arose during yesterday’s follow-up visit with Dr. David Pfister, my medical oncologist at Memorial Sloan-Kettering Cancer Center (MSKCC). Separate from my upcoming daily radiation treatments, the appointment largely focused on scheduling my three chemotherapy infusions and discussing what to expect in terms of side effects from the treatment. The chemotherapy I will receive is called cisplatin, which was first approved for use in testicular and ovarian cancers back in 1978. The list of potential toxicities includes nausea, constipation, kidney issues, hearing issues, and others. The conversation shifted to potential clinical trials and Dr. Pfister mentioned one that is exploring an alternative to chemotherapy that may have less side effects. In the study, the chemotherapy agent (cisplatin) is replaced by Erbitux® (cetuximab) – another FDA approved agent for treating head and neck cancer. Erbitux is an inhibitor of the epidermal growth factor receptor (EGFR), a receptor found on both normal and tumor cells that is important for cell growth. But the study also adds an investigational agent BYL719, which is an inhibitor of PI3K, an enzyme which fuels the growth of several types of cancer. Having worked at several companies developing inhibitors of the PI3K pathway, this was more familiar territory. However, trading the proven results with cisplatin for “potentially” similar efficacy with lower side effects from the investigational combination is a difficult crossroad.
On the one hand, the aforementioned clinical trial includes an approved agent for treating head and neck cancer (Erbitux). This is different from some other clinical trial designs that include a placebo arm or an arm with only an investigational agent. However, Erbitux has its own side effects and there are unanswered questions in the medical community regarding whether or not Erbitux is “as good” as cisplatin. As a result some physicians only use Erbitux as a replacement for cisplatin when the patient cannot tolerate cisplatin’s toxicities. In my mind, forgoing cisplatin and its proven efficacy could jeopardize the potential for cure. Partially offsetting this risk is the inclusion of a promising new investigational agent – the PI3K inhibitor BYL719 being developed by Novartis. The PI3K pathway is widely known in the oncology community as a potential target for cancer therapy – and in particular head and neck cancer. Preclinical data suggest that simultaneous inhibition of PI3K and EGFR leads to synergistic antitumor activity in head and neck cancer, but future randomized trials are required to answer the question of whether or not the combination is equal to (or better than) cisplatin. Lastly, BYL719 is an investigational agent and although it appears well-tolerated in studies to date, side effects may arise as more and more patients are exposed to the drug.
Ultimately, I decided to stick with the more established cisplatin for a variety of reasons. First, it is my understanding that the radiation therapy, which would be included regardless of whether I opted for cisplatin or the investigational Erbitux/BYL719 combination, is the driving force for both cure AND debilitating side effects. Most of cisplatin’s side effects, such as nausea, constipation, and other issues, can be partially offset with medication and hydration. Second, cisplatin has been around for decades and appears to be the gold standard in combination with radiation for Stage IV head and neck cancer and it is hard to argue with the clinical data supporting its use to date. Lastly, in the unfortunate event that my chemoradiation therapy isn’t effective – I can always explore investigational treatments as a next step.