Are Sponsors Downplaying Risks of Cancer Drugs?

According to a recent research effort by Bishal Gyawali and colleagues, clinical trial sponsors may be using terms that downplay or minimize the risks and seriousness of adverse events for certain cancer drugs.  All of these studies were published in top medical journals. The authors raise awareness with example treatments in the table below.

Sponsor Drug Description Sponsor Position Transparency Issues
Astex Pharmaceuticals


Ribociclib (Kisqali) It is an inhibitor of cyclin D1/CDK4 and CDK6 and is used for the treatment of certain kinds of breast cancer. Furthermore, it is being considered for other drug-resistant cancer treatments. “Most patients had an acceptable adverse-event profile” More than twice as many patients in the ribociclib arm as in the control arm experienced severe (grade 3 or higher) adverse events (271/334 v 108/330)

The difference in treatment related serious adverse events (leading to death, life threatening condition, hospital admission or prolonged admission, disability or permanent damage, congenital anomaly or birth defect, or that required medical or surgical intervention to prevent one of the other outcome

Pfizer Irinotecan (Campostar) Medication used to treat colon cancer and SCLC. “has a manageable and mostly reversible safety profile” In fact, five patients in the intervention arm died from drug toxicities versus none in the control

Active Biotech Research AB

Tasquinimod Experimental drug currently being investigated for the treatment of solid tumors. Tasquinimod has been mostly studied in prostate cancer, but its mechanism of action suggests that it could be used to treat other cancers. “Tolerability was good overall” The incidences of severe and serious adverse events compared with control were 42.8% v 33.6% and 36.0% v 23.6%, respectively


The authors demonstrated only a few examples of this issue, and there may be many more. The adverse event dynamics of possibly many new oncology drugs, they argue “are hidden behind similarly general or subjective terms that obscure their harms.” Follow the link to BMJ and read the entire study for those interested in this important topic concerning new cancer drugs.

Lead Research/Investigator

Bishal Gyawali