Source: National Cancer Institute.

The past week on Wall Street has been downright ugly. For five straight sessions panic has pushed all three major market indexes lower by double-digit percentages.

Although stock market corrections are a perfectly normal and healthy thing for the market, investors generally loathe their arrival since it generally means a drop in the value of their portfolios. But one sector where corrections are a particularly unwelcome sight is biotechnology.

"Why biotech?" you wonder? Because biotech is arguably one of the priciest sectors in the market, and also one of the toughest to value. Traditional metrics don't often work with biotech stocks since nearly 90% aren't profitable. Instead, emotions and estimated future sales of drug developers' product portfolios and pipelines play a big role in determining biotech stock valuations. Unfortunately, when emotions come into play, as they have during this correction, it can mean exacerbated moves lower (and higher) for biotech stocks.

These biotech stocks bucked the stock market crash
Out of the 155 biotech stocks with a market valuation in excess of $300 million, 145 have moved lower over the past week. Yet that also means that a select group of biotech stocks have looked this dramatic sell-off right in the eye and come out greener on the other side. Here are three such biotech stocks that have thus far been able to buck the stock market crash and head higher.


Source: U.S. Food and Drug Administration.

Lexicon Pharmaceuticals (NASDAQ: LXRX)
The most impressive biotech stock of them all is surprisingly one of the decade's biggest laggards: Lexicon Pharmaceuticals.

Over the past week shares of Lexicon have risen 14% as a continuation move from the early August announcement that telotristat etiprate, an oral treatment for cancer patients with carcinoid syndrome that isn't adequately controlled by the current standard of care, met its primary endpoint in the phase 3 TELESTAR trial. Both doses of the experimental drug (250 mg and 500 mg) led to a statistically significant decline in the number of average daily bowel movements over the course of the 12-week study.

The news was fantastic for Lexicon, which currently lacks a marketed product. Although the Food and Drug Administration will have the final say, it would appear that Lexicon will finally be generating recurring revenue as early as the first half of next year.

Another pipeline product that I find even more exciting is sotagliflozin (formerly LX4211), an oral small-molecule drug that's an inhibitor of SGLT-1 and SGLT-2 for types 1 and 2 diabetics. We've already witnessed a handful of SGLT-2 inhibitors approved by the FDA, but we haven't seen a company really aim to target both SGLT-1 and SGLT-2 to help better control glycemic balance.

Of course, Lexicon is also valued at $1.25 billion despite being a ways off from having any chance at profitability. So, in spite of its strong performance over the past week and in the entire month of August, your smartest bet might be to remain on the sidelines until we have more data on sotagliflozin or a guaranteed approval for telotristat etiprate.

La Jolla Pharmaceutical (NASDAQ: LJPC)
La Jolla Pharmaceutical, which had also been written off by investors until recently, is a wholly clinical-stage biotech company. But unlike Lexicon, which has an ongoing mix of orphan and chronic disease research, La Jolla Pharmaceutical focuses almost entirely on rare disease indications. The advantage to this is it removes the likelihood of competition and can help inflate the price tags for an approved therapies since few, if any, other treatments may exist.

Source: Vanderbilt Health.

Over the past week La Jolla Pharmaceutical has jogged higher by 9% after it announced that two small-molecule kinase inhibitors were granted the orphan drug designation for fibrodysplasia ossificans progressiva, a genetic disorder where the body turns muscle into bone. Additionally, La Jolla Pharmaceutical and Vanderbilt University entered into a research and licensing agreement related to small-molecule kinase inhibitors specifically designed to block the bone morphogenetic protein type-1 receptor family. Long story short, more progress in rare disease innovation.

What shareholders are really eyeing, though, is an ongoing phase 3 study known as ATHOS involving LJPC-501 as a treatment for a rare low-blood pressure condition, catecholamine-resistant hypotension (CRH). The primary endpoint of the study is an increase in blood pressure, with the top-line results expected by the end of next year. While difficult to predict because CRH is pretty rare, varied estimates on Wall Street suggest the drug could net a half-billion dollars in peak annual sales if approved.

But La Jolla Pharmaceutical has already had quite the run. Shares are up 175% over the trailing year, and there are few guarantees that its pipeline will be a success. Until shareholders have the top-line data from ATHOS in-hand, it might be best to sit this one out as well.

Acorda Therapeutics (NASDAQ:ACOR)Finally, mid-cap biotech Acorda Therapeutics has trudged higher by 1% over the past week, mostly due to Tuesday's welcome stock price surge following news that the Patent Trials and Appeal Board (PTAB) had declined to institute the inter partes review request for two patents concerning multiple sclerosis drug Ampyra.

(NASDAQ:ACOR)

Source: Acorda Therapeutics.

If you recall, back in April The Wall Street Journal singled out Kyle Bass, hedge fund manager at Hayman Capital Management, for his unique method of investing. Bass was targeting patents which he believed had little to no value and attempting to invalidate them, while also short-selling the stock of any company's patent he challenged. One of those companies was Acorda Therapeutics. Considering that the PTAB found no merit in Bass' request, it could wind up setting a precedent and shooting down his entire short-selling thesis.

With that gray cloud lifted, investors can again turn their attention to Acorda's growing top-line (which is pretty much all Ampyra). In its latest quarter, Ampyra sales grew to $105.5 million from $87.4 million in the year-ago quarter, with the company slightly boosting its full-year Ampyra sales guidance to a new range of $410 million to $420 million from a prior forecasted range of $405 million to $420 million. With Acorda healthfully profitable in the highly lucrative MS space, I'd suggest there could be modest upside from its current share price.

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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