The Dow Jones Industrial Average (INDEX: ^DJI) rallied on the last day of the week, closing up 186 points as EU leaders put another Band-Aid on the ongoing fiscal crises in the region. As volatile as the broader market was, significantly larger moves happened in the health-care sector. For instance, Adeona Pharmaceuticals (AMEX: AEN) jumped up 12% on five times its normal trading volume despite the absence of any news.

Let's focus on two biotechs that made moves because of breaking news.

Cell Therapeutics (Nasdaq: CTIC) announced that the company is raising $20 million via an equity offering. Shares plunged nearly 15%. This came as a real slap in the face to investors reveling in the 24% gain the company achieved after the FDA accepted the application of pixantrone earlier in the week. This is Cell Therapeutics' second dilutive offering in six months! The company needs more cash to advance pixantrone if it is approved, but why do it now? With a cash burn rate of about $15 million a quarter, it could have made it to the FDA decision -- which, if positive, would send shares substantially higher.

Investors also need to set reasonable expectations for what a positive approval means. As fellow Fool Brian Orelli points out, pixantrone is a third-line treatment, so the type of blockbuster enthusiasm that sent Dendreon (Nasdaq: DNDN) soaring is likely off the table. Spectrum Pharmaceuticals (Nasdaq: SPPI) and its modestly successful cancer drugs Zevalin and Fusilev are likely a better analog, which would still be more than a double for Cell Therapeutics investors... if everything goes well from here on out.

And at the opposite end of the spectrum we have SIGA Technologies (Nasdaq: SIGA) and its marketing partner PharmAthene (AMEX: PIP) soaring 32% and 15%, respectively. A CNN interview with SIGA director Fran Townsend quashed rumors of impropriety concerning the company's lucrative government contract, easing investors' biggest worry.

The two companies' relationship would fall under the "it's complicated" status on Facebook after SIGA canceled a merger with PharmAthene once it realized how valuable smallpox antiviral drug ST-246 was. PharmAthene recently won a court verdict affirming its right to a portion of the drug's profits. Although the legal wrangling could continue, today's pop is still excellent news for both companies, and investors should be able to relax and enjoy the weekend.

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