Clinical Brief – October 2nd
ESMO, or the European Society of Medical Oncology Congress, is an annual gathering of cancer experts and patient advocates. Here are some studies from this year’s ESMO that may be of use.
Drug interactions range from those that are harmless, to ones that pose serious risks that could put someone in a hospital. So, does a given cancer med have potentially worrisome drug interactions?
Look it up on Cancer-Druginteractions.org.
This freely available site is modeled off of a well-known site geared towards HIV meds. It’s so simple that any well-educated patient can navigate this. In fact, I would personally recommend this to people living with cancer around me to ask that they flag any potential drug interactions to their physicians and pharmacists for investigation.
“The freely available, independently developed website with ‘traffic light’ classification will facilitate healthcare professionals’ and patients’ awareness of potential drug-drug interactions between oncolytics and frequently used comedications.”
– Lankheet NAG, et al.
Hats off to researchers from Radboud University Medical Center Nijmegen and Deventer Hospital, both of the Netherlands, and the University of Liverpool, UK.
In terms of trends, these researchers also found that of over 450 potential drug-drug interactions between cancer meds and other drugs, targeted therapies generally posed a greater problem than monoclonal antibodies (a type of biologics).
Cannabis may be linked to dampened tumor response to nivolumab (Opdivo), say researchers at the Rambam Health Care Campus, Israel.
They looked through records of 140 patients treated at their hospital for melanoma, non-small cell lung cancer, or kidney cancer. About two-thirds were on nivolumab alone and one-third were taking nivolumab with cannabis. It’s not clear if cannabis was inhaled or ingested.
Patients taking nivolumab with cannabis had less than half the tumor response rate than their non-cannabis using counterparts (16% vs 38%).
On the brighter side, progression-free survival and overall survival were not significantly different between patients who took cannabis vs those who didn’t.
Still, the magnitude of tumor response rate difference flagged here warrants further investigation. I’d be interested if other hospitals see similar trends and if so, perhaps we should look at potential causes.
Chances are, you’ve heard of cooling caps being used to reduce the risk of chemo-induced alopecia. The idea is that by dropping the temperature, blood flow would drop and cells would divide slower – both of these should lead to less chemo exposure to healthy cells.
Now, researchers from the Netherlands bring you “frozen gloves” in a bid to mitigate chemo-induced nerve damage.
For their trial, they recruited 180 patients newly diagnosed with cancer due to receive combination chemo. Patients were randomized 50/50 to wear frozen gloves or not, while they got their infusions. Well actually, the abstract says “during treatment”. I don’t know how cold these frozen gloves are, but I doubt they had their patients wear them every day for weeks if not months. But I could be wrong.
More importantly, does it work? Sort of.
They looked for patients reporting tinging in their fingers and hands as a sign of nerve damage. After 3 cycles of chemo, significantly fewer patients wearing frozen gloves felt tingling in their fingers and hands than those who didn’t wear them (11% vs 24%). At the end of treatment, still fewer patients wearing frozen gloves felt tingling in their fingers and hands than those who didn’t’ wear them (28% vs 43%).
After 6 months, the number of patients reporting tingling in their fingers and hands drops and the difference between those who wore frozen gloves vs those who didn’t disappears.
Is it worth the trouble? That probably depends on the patient.
On the one hand, patients wearing frozen gloves reported better quality of life metrics during treatment vs those who weren’t wearing them. On the other hand, there were no long-term benefits and about a third of patients stopped wearing frozen gloves because they were uncomfortable. Pun intended.
Sometimes, it’s not just the number of drug interactions that matter, but the potential side effects they cause.
Taking cetuximab (Erbitux) with a proton-pump inhibitor (or PPIs) may be linked to an increased risk of rashes and low blood magnesium levels.
Researchers from Rambam Health Care Center, Israel, found that among nearly 120 patients treated with cetuximab at their hospital, more patients taking a PPI reported a skin toxicity than those who weren’t (57% vs 37%). The difference was more drastic when only moderate or severe cases of skin toxicity were counted (33% vs 3%).
On average, severe skin toxicity was detectable after 22 days of treatment.
Low magnesium levels followed what appeared to be a similar trend. More patients taking a PPI with cetuximab experienced this side effect vs those who weren’t on a PPI (26% vs 10%).
Like their other study with nivolumab and cannabis, this is data from a single hospital. If other hospitals share similar experiences, a prospective trial is definitely called for to further investigate this potential drug interaction.
IV glutamine may help prevent or delay radiation-induced mucositis for patients with head-and-neck cancer.
Researchers from the Tanta University Hospital, Egypt, ran a Phase II trial where 100 patients with head-and-neck cancer due to receive radiation treatment were randomized 50/50 to also receive L-alanyl L-glutamine or not.
Fewer patients who got glutamine with their radiation therapy had mucositis vs those who didn’t get glutamine (10% vs 45%). On average, they also enjoyed an extra 4 weeks of being free of mucositis vs those who didn’t get glutamine (median time free from mucositis: 12 vs 8 weeks).
Also clinically relevant was that fewer patients who got glutamine with their radiation treatment needed treatment interruptions than those who didn’t get glutamine (15% vs 50%).
“No adverse effects were observed in relation to glutamine.”
– Eifeky AM, et al.
Now, the one thing that this study missed was a placebo control. If only they gave saline to the other half! So, we cannot rule out the possibility of a placebo effect here.
That said, I’m always keen to exploit placebo effects. If it helps, who cares if it’s placebo? Still, given these promising results, a proper controlled (and blinded) trial should be done.
I’m also a bit skeptical about the safety profile. It may be that the trial was too small to catch anything that may not seem obvious right away.
For more presentations from #ESMO17, take a look at my hand-curated Twitter moment 🤓.