Pharmacyclics (NASDAQ:PCYC) did the "little stock that could" routine on Tuesday, chugging furiously to rest among the most active stocks of the day. The cause of all the hullabaloo? News that the Food and Drug Administration had granted fast-track status for its investigational cancer drug Xcytrin.

The stock jumped 25% in Tuesday's trading, with volume at 10.5 million shares, compared to its average daily volume of just 47,000.

Xcytrin is an injection that gets inside cancer cells, disrupting metabolism and eventually killing those cells. The application currently enjoying fast-track status treats brain metastases in patients with small-cell lung cancer.

Possible cancer treatments are always exciting. As the second-leading cause of death next to heart disease, it's definitely one of the big, bad illnesses that we'd all like to see combated with successful treatments. According to the American Cancer Society, brain tumors account for about 1% of cancers and 2% of cancer-related deaths.

Fast-track status indicates that Xcytrin has shown some promising results, and gets the company's drug a higher level of attention from the FDA and the possibility of earlier approval. As exciting as the news is, though, the fast-track status does not guarantee approval for the drug.

In addition, the upbeat news doesn't change the fact that this is not yet a profitable company. For the quarter ended Sept. 30, Pharmacyclics reported a loss of $7.2 million, compared to a loss of $6.7 million for the same quarter of last year.

A look at Pharmacyclics' 10-K revealed some concerns of a competitive nature. For example, Allos Therapeutics (NASDAQ:ALTH), another small biotech firm, is developing a drug with similar properties that may prove a serious rival. In fact, on Nov. 17 Allos announced that it had been granted fast-track designation from the FDA for its treatment for brain metastases associated with breast cancer.

Despite the promising news and the positive market attention Pharmacyclics received Tuesday, there are still plenty of reasons why taking a shot at the stock remains risky.

Discuss the latest in drug development on the Fool's Biotech discussion board.

Alyce Lomax welcomes your feedback at alomax@fool.com.