Photo credit: James Gathany

1. Government researchers in the U.S. have started a clinical trial for a Zika vaccine. The study is funded by the National Institute of Allergy and Infectious Diseases and will involve at least 80 healthy volunteers between the ages of 18 to 35 years old. (Reuters)

2. Aetna said it is contacting physicians whose prescribing habits for opioid painkillers fall outside the norm. The insurer sent letters to 931 physicians who fill opioid prescriptions at higher rates compared to their peers. (WaPo)

3. About half of all pediatric clinical trials are discontinued or conclude without publishing results, according to a new analysis. Trials funded by industry are more likely to be completed than ones funded by academia. (Stat)

4. Biosimilars are just as effective as their brand-name counterparts, a study found. Researchers examining biosimilars for rheumatoid arthritis, inflammatory bowel disease, and psoriasis treatments found that they were just as effective as biologic versions of the drugs. (International Business Times)  

5. Novo Nordisk’s diabetes drug Victoza did not show improved heart function in patients with advanced heart failure, according to a new study. Some patients in the study experienced slightly higher risk of death, re-hospitalization, and kidney malfunction. (U.S. News and World Report)