An Issue of Cost
Given those and other promising results, why are oncologists still using BSA for dosing cancer drugs?
“There’s no doubt at all that it is very cheap to get someone’s height and weight and stick it in an iPhone app. That is certainly part of it. But we really don’t have a hard time spending money to individualize oncology care. I know we should be better at it,” Howard McLeod, PharmD, director of the Institute for Pharmacogenomics & Individualized Therapy and the Fred Eshelman Distinguished Professor of Pharmacogenomics and Individualized Therapy at the UNC Eshelman School of Pharmacy at the University of North Carolina at Chapel Hill told GEN.
He noted that doctors will order a radiologist to perform a scan for whether patients need a different dose of chemo, in the $1,500 to $3,000 range. However, from a cost standpoint, not enough solid data exists to determine the return on investment for using these chemotherapies according to BSA-based dosages.
“With insurance companies, part of the discussion is, ‘Can we show that we’re at least giving the patient optimal blood levels, and therefore maximizing the chance of benefit?’ If you’re an insurance company, you don’t like to spend a lot of money on chemo. But you especially don’t like spending a lot of money on chemo if you don’t know if the patient’s going to benefit,” Dr. McLeod said.
“The oncologists don’t like to have that discussion. But the insurers do. They need to have that. If we’re going to spend a lot of money on chemotherapy, we need to do everything we can to make sure that it’s not being wasted.”
Indeed the cost focus of insurers may well force oncologists to join their colleagues in other medical specialties in embracing MTE-based dosing over BSA, since toxicity and underdosing often lead to costlier care for patients given the wrong dose.
Another factor that will eventually limit costlier care for misdosed patients is whole-genome screening for patients with rare tumors, where there’s no known treatment or no effective treatment. “In the future, with genomic testing to identify drugs that may work, and by appropriate dosing, I think both of those things are going to be important for really making precision medicine something that is really carried out by doctors in the future,” Dr. Bertino said.
Genomic testing is now costly—$7,000–$8,000 per whole genome, or $1,000 to test 300 genes involved in sensitivity or resistance to drugs, Dr. Bertino said. But those prices are expected to fall as the era of the $1,000 genome finally becomes reality—whether it really happens by year’s end as predicted earlier this year, or soon after.