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.

What: Shares of biotech firm Halozyme Therapeutics (Nasdaq: HALO) are continuing their streak of wild price swings -- this time to the upside by as much as 27% -- after the company reported better-than-expected second-quarter results.

So what: For the quarter, Halozyme reported a loss of $0.13 compared to a year-ago profit of $0.03, on revenue of $7.8 million, primarily from exclusivity fees and research and development reimbursements. While they're not much to look at, these results slid past Wall Street's expectations to the upside. In addition, Halozyme's pipeline update got investors excited. It noted that Roche's (OTC: RHHBY) phase 3 study of the subcutaneous formation of MabThera (which uses an enzyme supplied by Halozyme) met its end goal. Halozyme also noted in a study that preadministration of recombinant human hyaluronidase (rHuPH20) may help type 1 diabetes patients absorb glucose better after a meal.

Now what: Today's 27% move higher brings a much-needed sigh of relief for investors who witnessed their stock lose half of its value last week following a rejection by the Food and Drug Administration for HyQ, which combines an immune globulin made by partner Baxter International (NYSE: BAX) and Halozyme's rHuPH20. The FDA requested additional preclinical data to support the findings of the drug, while also requesting a trial be stopped that combined rHuPH20 with ViroPharma's (Nasdaq: VPHM) Cinryze due to safety issues.

It's been a confusing and wild week to say the least! Personally, I've been notably pessimistic on Halozyme for some time and feel the company has a lot to prove in regard to controlling its cash burn rate and translating drug approvals into steady cash flow. Needless to say, I don't personally see today's news as a buying opportunity.

Craving more input? Start by adding Halozyme Therapeutics to your free and personalized Watchlist so you can keep up on the latest news with the company.

Fool contributor Sean Williams has no material interest in any companies mentioned in this article. You can follow him on CAPS under the screen name TMFUltraLong, track every pick he makes under the screen name TrackUltraLong, and check him out on Twitter, where he goes by the handle @TMFUltraLong.

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