BOSTON ( TheStreet) -- This week's Biotech Stock Mailbag opens with a question from @Nixon786:"Why is Xoma up 50% for the month?" The spark that sent Xoma ( XOMA) shares higher was the $40 million financing announced March 6. Normally, dilutive financings undertaken by money-losing biotech firms don't send stock prices higher. That's particularly true for companies like Xoma with a sad history of drug development futility. What's different here is that Baker Bros., a well-respected and closely followed health-care hedge fund, bought half the Xoma deal. RA Capital, a Boston-based hedge fund, was also a buyer of Xoma shares in the offering, according to regulatory filings. When Baker Bros. buys, other investors follow, especially when Baker Bros. buys big. The fund now owns about 20% of Xoma and I'm told will likely get a board seat. The fund tends to take large, long-term positions in drug and biotech companies it likes, including Seattle Genetics ( SGEN), Incyte ( INCY) and Viropharma ( VPHM). The question you're probably asking now is, "Wait a second -- Xoma? What the hell can Baker Bros. see in Xoma?"
Owen S. asks: "What are your predictions for the FDA drug approvals next week involving MAP Pharmaceuticals ( MAPP), Affymax ( AFFY) and Chelsea Therapeutics ( CHTP). And how do your predictions match up with investors you talk with on Wall Street?"