Alnylam Slide
Source: Alnylam Pharmaceuticals.

Being a socially responsible company is not a zero-sum game, where the more socially responsible you are, the worse your financial performance is, and vice versa. Profits don't go out the window when you treat the environment better. And similarly, socially responsible investing is not a zero-sum game, where the more socially responsible you are, the worse your portfolio's performance is. So go ahead and consider investing in some socially responsible companies – like Alnylam Pharmaceuticals (NASDAQ:ALNY).

In general, socially responsible investments can be quite competitive with their counterparts. A 2011 study  from Harvard Business School, for example, looked at 18 years of data and found "strong evidence that firms emphasizing [socially responsible] practices significantly outperform similar firms that do not, as measured by both financial and stock market returns." Meanwhile, a 2014 study by the folks at asset-management firm New Amsterdam Partners found "a positive linkage between stocks with higher ESG [environmental, social, and governance] ratings and superior returns and reduced price volatility."

Alnylam
Source: Alnylam Pharmaceuticals.

Why might you invest, or not invest, in Alnylam Pharmaceuticals?
Founded in 2002 and based in Cambridge, Mass., Alnylam Pharmaceuticals is a biotech company specializing in RNAi, or RNA interference, "gene silencing" technology. It aims to advance RNAi therapeutics as a new class of innovative medicines. The company primarily targets rare diseases but is also tackling conditions such as hepatitis B. My colleague Maxx Chatsko has explained the technology a little more clearly: "[T]he company can turn on genes needed for proper bodily function (genes making vital proteins) and/or turn off genes at the root of a disease (genes making faulty versions of critical proteins)."

Alnylam sports a market capitalization of $7 billion, and it has been rewarding shareholders for quite a while, with its stock up more than 60% over the past year and averaging annual gains of about 33% over the past decade. It has partnered with some deep-pocketed pharma companies such as Merck and Sanofi, which hold stakes in Alnylam.

Of course, the stock isn't perfect. Over the past decade, the company's revenue went up and has recently been declining while losses have been accelerating. It's burning cash rather than generating free cash flow. That's not shocking or necessarily terrible, as young biotechnology firms are typically investing heavily in developing technologies and therapies that will, they hope, eventually gain FDA approval and then sell well, generating big profits. But Alnylam isn't there quite yet.

Still, there are promising signs, such as its surpassing its "Alnylam 5x15" strategy, introduced in 2011, that had it aiming for five RNAi therapeutic programs in clinical development by 2015. It's now aiming for six or seven. One of them, patisiran, a treatment for transthyretin-medicated amyloidosis in patients with familial amyloidotic polyneuropathy, gave the stock a big boost last month, when Alnylam announced positive six-month phase 2 clinical results.

Alnylam Placeholder Photo
Source: Alnylam Pharmaceuticals.

What's so socially responsible about Alnylam Pharmaceuticals?
At CSR.hub.com, Alnylam Pharmaceuticals gets an above-average overall rating for social responsibility, handily topping category averages for employees and the environment, while lagging them in governance and community.

Wha, exactly are some things that Alnylam is doing or has done to earn its good marks? Well, for starters, back in 2009 it joined GlaxoSmithKline in fighting neglected tropical diseases. Alnylam donated more than 1,500 issued or pending patents on its RNAi technology to a patent pool started by GlaxoSmithKline.

On the employee front, the company's benefits are quite generous, including stock options, the ability to buy company stock at a 15% discount (though that's not always a wise thing to do), and $30 per month toward gym memberships.

Alnylam Pharmaceuticals offers a lot to be optimistic about, but its stock doesn't appear to be a screaming bargain at recent levels, and it's worth remembering that it doesn't have approved drugs on the market yet. Still, it's worth adding to your watch list -- or perhaps buying a few shares of, if you're quite risk-tolerant.

Longtime Fool specialist Selena Maranjian, whom you can follow on Twitter, has no position in any stocks mentioned. Nor does The Motley Fool. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.