Dyax (NASDAQ: DYAX) has some exciting opportunities ahead. These include an early stage drug that could be poised to radically shift the hereditary angioedema, or HAE, treatment landscape; a diversified pipeline full of drugs licensed to other companies; and an already-marketed product. But given the company's valuation, is now the time to buy?

A drug with solid potential
Let's start with the basics. DX-2930, a monoclonal antibody designed to prevent HAE attacks, is key to the Dyax investing thesis. Dyax recently reported encouraging phase 1b data for the drug. The trial results showed DX-2930 to be well tolerated and potentially effective, with two dosing groups -- 400 mg and 300 mg -- demonstrating statistically significant 88% and 100% reductions in HAE attacks, respectively, compared to the placebo.

While this is very early stage data based on a tiny sample of 37 patients, it's still exciting news and highlights DX-2930's potential for improving patient quality of life. The drug received Food and Drug Administration fast track and orphan drug designations; while that doesn't guarantee approval by any means, it indicates the FDA is willing to work closely with the company and sees the drug as a potential step forward from the current standard of care. Orphan designation is also given for rare diseases -- and with prevalence of between 1 in 10,000 and 1 in 50,000, HAE fits the bill. Plus, with analysts estimating roughly $500 million in peak annual sales in a market worth around $1 billion overall, DX-2930 could be a big needle mover.

But Dyax is bigger than that
One of the most difficult and frustrating things about biotech investing is that you're often betting the farm on a single (often early stage) drug. Dyax doesn't have that problem.

Now, DX-2930 is certainly a key part of any Dyax investing thesis, and the drug has plenty of chances to fail completely before actually making any money.

But it's not Dyax's only iron in the fire. The company also has a large and robust licensing and funded research portfolio -- containing nine drugs -- which it monetizes by licensing out the drugs to a variety of other pharma companies -- to the tune of about $4 million last quarter. While that may not seem like a lot of money, these are mostly early and mid stage drugs, so the money opportunity should grow as these drugs creep toward -- hopefully -- approval and commercialization. This portfolio is led by Cyramza, a drug licensed to Eli Lilly that is approved for several types of cancer and is in clinical trials for several more. Dyax also sells Kalbitor, a drug for treating HAE attacks, with revenue hitting $16 million last quarter. The company has guided for Kalbitor to bring in between $60 million and $70 million in 2015.

Still, that is not enough to balance out the expense of drug development -- Dyax's CFO recently estimated that, even with all of that revenue, Dyax will still be left with a burn of $20 million to $25 million in 2015 -- but it helps mitigate what would otherwise be an even greater cash outflow. And with over $180 million on the balance sheet, Dyax has a long runway ahead before additional share dilution would become a likely concern.

Balancing the scales
On one hand, you have a company with a diverse pipeline and revenue streams, an exciting (if still early stage) drug for HAE attack prevention, and a great potential growth path ahead. But you pay for quality, and with a $3.8 billion market cap, Dyax trades at seven times its projected sales for 2019 (according to analyst estimates, courtesy of S&P Capital IQ). Looks like heavy expectations are already built into the price. That's not my cup of tea -- I'd say the company is too expensive given the stock's revenue opportunities. DX-2930 is also a little too early stage for my taste, and I'd like to see results from a bigger trial before dipping my toes in. But Dyax is definitely a watchlist candidate, and if you're less risk-averse than I am and have a long-term investing horizon, this might be a good biotech to buy.