Two programs are underway to track off-label use of targeted cancer drugs and patient outcomes, as well as facilitate patient access to these agents.
According to Nature News, more than 60% of US prescriptions for cancer drugs are for off-label use—often because patients have a tumor with a feature or mutation targeted by a particular drug, but the drug has not been approved by a regulatory agency for that specific cancer. Outcomes of these patients are not currently tracked in a systematic manner.
Thousands of small-scale experiments are going on all the time in clinics and hospitals, but “we haven’t been able to learn from them”, Amy Abernethy, an oncologist at Duke University, told Nature News.
On 21 November, researchers at the annual Conference on Clinical Cancer Research presented 2 programs aiming to capture data from some of these experiments.
The American Society for Clinical Oncology (ASCO) is launching a first-ever study that will offer cancer patients access to targeted cancer drugs and collect real-world data on their outcomes. This study will help oncologists learn effects of these drugs outside of approved indications, ASCO Chief Medical Officer Richard L. Schilsky said at the conference.
One goal of the study is to create databases so that oncologists and scientists can search not only for potentially effective treatments, but also for clues as to why individual cancers are resistant or susceptible to drugs.
Although it is legal for physicians to prescribe drugs off-label in the US, such use is often controversial, and drug-makers are penalized if they promote their products for unapproved uses.
However, off-label regimens are likely to become more prevalent as more drugs begin to target genetic features of individual tumors. Currently, drugs can be approved only for the cancers in which they have been tested, even if the mutation that they target is shared by several tumor types. Vemurafenib and dabrafenib, for example, target a mutation in BRAF, and have been approved to treat melanoma, but not lung or thyroid cancers with the same mutation.
The problem is partly one of numbers, Schilsky told Nature News. “There are not enough patients and money to test every drug in every subtype of cancer using a randomized clinical trial”.
To address this shortcoming, Schilsky is spearheading a program called the TAPUR (Targeted Agent and Profiling Utilization Registry) study, to be launched in mid-2015. The study, run by ASCO, will compile information about treatments, outcomes, and mutations in people who have exhausted conventional therapies and moved on to unapproved treatments.
A similar effort, led by Dane Dickson, director of clinical science for molecular diagnostics at Palmetto of Columbia, South Carolina, has brought together pharmaceutical companies, researchers, and patient advocates to create another registry that aims to collect data on off-label use. This program, called the Molecular Evidence Development Consortium (MED-C), will collect information on drug effects and will also attempt to streamline and unify diagnostics, increase the numbers of patients screened and enrolled in clinical trials, and reduce the costs of molecular research.
According to Nature News, the MED-C program will require every study participant to undergo genetic testing so that researchers can compare results among genotypes and patient locations.
The TAPUR and MED-C programs are each in discussions with pharmaceutical companies to help to provide therapies at no cost to participants, in an attempt to motivate physicians to participate. In exchange, the companies have an opportunity to gather more data about their drugs.
The benefit for patients is clear, says Ellen Sigal, chairwoman and founder of Friends of Cancer Research, an advocacy group that co-hosted the conference with the Brookings Institution. “Off-label use is happening and we’d better figure out a way to get the data and do it in a meaningful way,” she told Nature News.