Biotech companies sometimes get lucky, launching a drug into a new indication where there's no competition, but more often than not the biotech companies have to battle it out with other drugmakers to reign supreme.

Here are three areas where biotech companies are facing head-to-head competition, along with some thoughts on who might ultimately win.

Help from a friend
VIVUS
(NASDAQ:VVUS) and Arena Pharmaceuticals (NASDAQ:ARNA) both launched obesity drugs within the last year.

In the short term, Arena has the clear advantage, simply because it has a larger pharma, Eisai, promoting the drug. It also doesn't have any restrictions on sales at pharmacies. VIVUS' Qsymia will only available at certified pharmacies, and it's going to take awhile to get them all certified.

For the longer term, Qsymia could gain the upper hand, especially if it can find a marketing partner, since the drug produces better weight loss -- albeit with additional potential side effects.

Of course, obesity is a large market. There's likely room for two biotech companies to have blockbuster drugs if they can convince doctors to prescribe the drugs and insurers to pay for them.

Adopting the orphan
Both Isis Pharmaceuticals (NASDAQ:IONS) and Aegerion Pharmaceuticals (NASDAQ:AEGR) gained approval for an orphan genetic disorder called homozygous familiar hypercholesterolemia, or HoFH.

While Isis has a marketing partner in Sanofi, that's less of an advantage for HoFH than it is for obesity where there's a lot more doctors seeing obese patients. Only 3,000 people in the U.S. have HoFH, so a large sales force isn't really needed.

I think Aegerion, which is going it alone, has the advantage because its drug is so much better. Juxtapid is taken orally while Isis and Sanofi's Kynamro has to be injected. Juxtapid also has less severe side effects, which should give the biotech company an advantage.

David and Goliath
Johnson & Johnson
may be three times the size of Gilead Sciences (NASDAQ:GILD), but the smaller biotech company should have no problem competing with Johnson & Johnson in the hepatitis C space.

Both companies recently submitted their second-generation hepatitis C drugs and should hear back from the Food and Drug Administration by the end of the year.

Gilead's sofosbuvir would be approved to treat patients infected with all the different genotypes of virus, while Johnson & Johnson's simeprevir is limited to just genotype 1 patients.

These drugs aren't the endgame for hepatitis C. They'll likely be used in combination with other drugs, which gives Gilead the clear advantage because it has an extensive pipeline of additional drugs to combine with sofosbuvir. Johnson & Johnson is counting on partnerships to fill that gap.

Fool contributor Brian Orelli has no position in any stocks mentioned. The Motley Fool recommends Gilead Sciences and Johnson & Johnson. The Motley Fool owns shares of Johnson & Johnson. Try any of our Foolish newsletter services free for 30 days. We Fools may not 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.