With the SPDR S&P Biotech Index up 30% over the trailing 12-month period, it's evident that investment dollars are willingly flowing into the biotech sector. Keeping that in mind, let's have a look at some of the rulings, studies, and companies that made waves in the sector last week.

Considering that we had the JPMorgan Healthcare Conference ongoing all week, there was absolutely no shortage of information and data being flung around by dozens of biotech companies. Since we've covered quite a few of the reporting companies and their presentations, here are a few of the more notable non-JPMorgan Conference stories that took center stage.

Peregrine Pharmaceuticals (NASDAQ:PPHM) was one of the week's biggest gainers following a clarification of problems with its clinical study of bavituximab, a second-line treatment for non-small-cell lung cancer. Peregrine shares imploded a few months back, after the company warned investors not to rely on its clinical data, but ultimately it appears that only the 1mg/kg dose subset was affected. According to Peregrine, its 3mg/kg dose subset of patients survived roughly 13 months since beginning the treatment. While I'd hardly call Peregrine a sure thing following this third-party mishap, it's a step in the right direction.

Shares of biopharma giant Johnson & Johnson (NYSE:JNJ) hardly budged this week, but it's worth noting that the FDA panel voted 10-5 in favor of recommending Invokana, its Type-2 diabetes SLGT-2 inhibitor, for approval. Although 10-5 isn't a ringing endorsement, and the FDA panel spent quite a bit of its review time contemplating the safety of Invokana on patients' hearts, this new type of inhibitor looks like it could capture quite a bit of the Type 2 diabetes market share if approved. As icing on the cake, J&J also received expanded approval in Europe to begin using its prostate cancer drug Zytiga earlier in the treatment process in combination with prednisone.

Although Novartis' (NYSE:NVS) Afinitor is already approved in the U.S. to treat kidney cancer, further clinical data published in The Lancet and highlighted by my Foolish colleague Dan Carroll demonstrates the effectiveness of the drug. According to data from the trial, Afinitor showed a significant reduction in kidney tumors due to tuberous sclerosis complex and exhibited a response rate of 42% versus 0% for the placebo.

On the other end of the spectrum, Merck (NYSE:MRK) announced yesterday that it'll pull its HDL cholesterol drug, Tredaptive, from market because it failed to reduce good cholesterol in patients and raised serious safety concerns in additional clinical trials. Although the side effects were non-fatal, they were still serious in nature, including blood, lymph, and gastrointestinal problems. Luckily for investors, Tredaptive, which is sold in 40 countries but isn't approved in the U.S., brought in only about $20 million in annual sales, so it won't be a big loss for Merck.

Finally, VIVUS (NASDAQ:VVUS) shares took flight after the company noted that in its most recent rolling four-week period, it shipped approximately 13,000 orders for its fat-busting drug Qsymia. That's a clean 68% improvement over the previous four-week period, as the company announced that 14,500 people have now been treated with the drug. Clearly, Aetna (NYSE:AET) and Express Scripts' (NASDAQ:ESRX) coverage of Qsymia is helping push the cost out of patients' pockets and toward insurers, which is making a big difference in VIVUS' bottom-line results.

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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