JPMorgan analyst Anupam Rama downgraded Dynavax to Neutral from Overweight after the FDA extended its review timeline for the company's Hepatitis B vaccine Heplisav by three months due to the agency's request for individual phase three data sets. While approval is still likely, the delay increases the risk of an advisory panel, Rama tells investors in a research note. The analyst reduced his probability of regulatory approval to 75% from 90%. This, coupled with concerns on the pace of Heplisav uptake in the key diabetic market, drives his downgrade and lowered price target of $22.