With the dearth of data that drugmakers release to investors about their compounds, it's understandable that investors can be a little jittery when a drug gets delayed. Shares of InterMune (NASDAQ:ITMN) fell more than 7% yesterday after an analyst predicted possible safety concerns causing a possible delay with the drugmaker's lead drug, hepatitis C drug candidate ITMN-191.

I used "possible" twice because everything the analyst stated in his report was conjecture about the reason why InterMune and partner Roche haven't started the phase 1b pharmacokinetic and efficacy study for ITMN-191 yet.

As recently as the May first-quarter earnings release, InterMune had stated that the phase 1b study would start in the third quarter with study results released in the fourth quarter, possibly at a medical conference in October or November.

There's no word yet on whether InterMune is sticking to this timeline. But even if there is a delay with ITMN-191, it shouldn't be too much of a concern for investors. InterMune has previously stated that it was revising the phase 1b study after learning more about the potency of the drug from the just-completed phase 1a safety study and from knowledge gained from Vertex Pharmaceuticals' (NASDAQ:VRTX) studies with its HCV compound.

Early-stage hepatitis C efficacy clinical trials typically track a small cohort of 30 to 70 patients over a 15-day period to track the initial viral load reductions and pharmacokinetics of the drug candidate at different dosages. With Roche's deep pockets and experience running clinical trials with the second-highest grossing HCV drug, Pegasys, the ITMN-191 phase 1b efficacy study won't have any problems enrolling patients or being completed in a timely manner.

For instance, the initial ITMN-191 phase 1a safety study clinical trial, which was done in 74 healthy volunteers, took less than five months from its initiation in December 2006 to the announcement of its completion in May. I'd be surprised if the phase 1b trial took as long, considering that it will be tested in a much more motivated patient population and the study results won't take long to analyze.

Shares of both InterMune and rival Vertex have lost over a third of their value since their 52-week highs. Investors looking to buy into the next blockbuster class of hepatitis C treatments on the cheap just got their chance.

InterMune and Vertex are Rule Breakers selections. You can check out all our recommendations as well as get access to our message boards and exclusive content with a 30-day free trial.

Fool contributor Brian Lawler owns shares of InterMune, but no other company mentioned in this article. The Fool has a disclosure policy.