Target therapy

Elderly patients with metastatic renal cell carcinoma (RCC) who are often ignored in clinical trials to treat the kidney cancer are seeing survival benefits from treatment with targeted therapies, according to a new study from Penn Medicine researchers. Analyzing 13 years of data on Medicare patients, the study found that the patients who receive target therapies; were more medically complex than those who receive the older, more toxic treatments that were available earlier in the study period; indicating that newer treatments are offering hope to more people.

Since 2005, the U.S. Food and Drug Administration has approve 12 target therapies for the treatment of advance RCC. However, clinical trials investigating these therapies often exclude sicker patients and those over the age of 65; leaving a gap in knowledge about the effectiveness of newer versus older treatments in this population; especially when they are treat in routine health care settings rather than in research studies.

Target therapy offer new treatment

Our findings suggest that target therapies offer new treatment options to elderly and medically complex patients; who may have otherwise foregone the treatments available 15 years ago given their high toxicity and limit benefit. RCC is a cancer where people can often try other treatment options if the first one isn’t effective; so even small gains may mean that a person might live long enough to try the next innovation. What’s more, studies are showing that current treatments, including immunotherapies; are leading to even better outcomes than those that were observe during our study time frame.” Senior author Jalpa A. Doshi, PhD, a professor of Medicine in the Perelman School of Medicine at the University of Pennsylvania.

Results also show that target therapies offer a modest survival benefit as compare to older treatments; even though as a whole, the target therapy treatment group had characteristics that put them at risk for worse outcomes. The researchers conduct a retrospective cohort study using Surveillance, Epidemiology; and End Results (SEER)-Medicare data from 2000 to 2013 to examine overall survival and estimated overall survival improvements in over 1,100 patients; with stage IV clear cell RCC who receive any FDA-approve target therapy (63 % of patients) or non target therapy (37 percent of patients).

The initial analysis found no statistically significant difference in survival between target and non-target therapies. However, a more in-depth analysis that used statistical techniques to mimic the more control conditions found in clinical trials known as an instrumental variable analysis; reveal a three-month survival advantage with target therapies compare to older treatments. Estimate overall survival improvements with target therapy versus non target therapies were also statistically significant eight % at one year; seven percent at two years, and five % at three years.

Sophisticate statistical method

“The more sophisticate statistical methods allow us to see an unbiased picture of how the treatments compare in the real world,” said first author Pengxiang Li, PhD, a senior research investigator at Penn Medicine. “The method help control for unmeasured differences between the treatment groups; which cannot be adjust using traditional approaches.”

Despite the findings, the median survival benefits observe in this real-world patient population were smaller compare  to the benefits; seen in clinical trial participants enroll in randomized studies of targeted therapies. The combined findings underscore that research studies summarize outcomes for groups of patients and may not accurately reflect how treatments will perform; in the real world or what any individual patient can expect from treatment. For example, in this study, half of the target therapy group had pass away within nine months; but 10 % of people survive longer than 47 months. Among that group with better outcomes, target therapies offer an 11-month survival advantage over older treatments; the researchers report.

“Treatment decisions involve weighing potential risks, benefits, and costs of treatment as well as quality-of-life considerations; which may vary from person to person depending on their medical situation and preferences. Good communication between patients and their treatment teams is essential, and knowing more about real-world outcomes can help with those discussions,” said co-author Amy R. Pettit, PhD, adjunct fellow at the Penn Center for Public Health Initiatives.