Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

Good morning, fellow Foolish investors! Let's take a look at the early movers in health care today.

Hep C treatment data boosts Enanta Pharmaceuticals 
Perhaps the biggest story of the day in health care is Enanta Pharmaceuticals (ENTA -0.76%) late-stage trial data for its all-oral hepatitis C treatment being developed by AbbVie (ABBV 0.20%). Enanta's therapy, currently known as ABT-450, was being investigated in three separate late-stage trials as a treatment of the most common form of hepatitis C, genotype I. What's important to key in on is the high sustained virologic response rates across the trials. Specifically, ABT-450 showed greater than 90% response rates within a twelve week time frame for all trials combined. Simply put, ABT-450 appears to be the latest all-oral functional cure for hepatitis C, and could be a major competitor to Gilead's Sovaldi in the near future.  

ImmunoGen's future looks bright
Shares of the monoclonal antibody maker ImmunoGen (IMGN) are also moving higher in premarket this morning after the company gave a particularly rosy outlook for 2014, and a stronger than expected earnings report. Namely, ImmunoGen beat earnings estimates by $0.22 last quarter, propelled by increasing royalty payments for its antibody drug conjugate, or ADC, Kadcyla licensed out to Roche

What's really exciting investors this morning, however, appears to be the large number of near-term clinical catalysts outlined in the earnings report. Chief among these catalysts, ImmunoGen announced that they will give a clinical update for their wholly owned ADC, IMGN529, indicated for CD37-positive B-cell malignancies by mid-2014.  

Is ImmunoGen worth keeping on your radar? I believe so. Major pharmas like Roche have helped to validate the ADC platform as an important new therapy for the treatment of cancer, and ImmunoGen is clearly a leader in this effort. So, you might want to dig deeper into this compelling biopharma going forward. 

Prana pulling back? 
Shares of the tiny Austrian-based Prana Biotechnology (NASDAQ: PRAN) are pulling back in premarket this morning following their monstrous 20% rise yesterday. The company's shares are now up an impressive 75% for the month of January alone.

Although it's difficult to pin this meteoric rise on a particular event, it's likely linked to the upcoming data release of the company's two mid-stage trials for PBT2, an experimental treatment for Alzheimer's disease and Huntington's disease. According to my Fool colleague Keith Speights, Prana's executive management have been traveling to discuss the trials with institutional investors lately, which has probably helped drive some of the recent movement.

In light of the stock's world beating month, today's pullback shouldn't come as a major surprise. That said, it's important to understand that Prana will need to raise a significant amount of cash to move PBT2 into late-stage trials, if the mid-stage data warrants such a development. Put simply, a secondary is highly likely in the near future. So, with that in mind, I think there will be better opportunities to buy Prana shares post-data release.