What happened

Shares of Biohaven Pharmaceutical (BHVN -0.47%) are on the move following a preliminary revenue report for the second quarter. Investors excited about Nurtec sales that outperformed expectations drove the stock 10.1% higher as of 11:25 a.m. EDT Wednesday. 

So what 

In May, the FDA approved Biohaven's lead drug, Nurtec ODT, to prevent migraine headaches in addition to its previous indication as an acute pain reliever. This made Nurtec the only CGRP inhibitor approved to prevent migraine pain and rapidly relieve that pain once it starts. It's also the only oral CGRP inhibitor approved at the moment.

Happy investors checking their holdings.

Image source: Getty Images.

Biohaven's stock price is surging Wednesday because preliminary second-quarter sales figures for Nurtec blew past analysts' expectations. During the period, net product revenue from Nurtec reached $93 million. That's a whopping 112% increase over the first quarter.

Now what

The post-label-expansion sales bump Biohaven reported Wednesday suggests there's a lot of demand among migraine headache sufferers for easy-to-swallow preventative treatment options. Pharmaceutical giants Eli Lilly (LLY -1.00%) and Amgen (AMGN -1.33%) launched injectible CRGP inhibitors in 2018. But despite Amgen having plenty of resources to fund new drug launches, sales of its contender, Aimovig, dipped in the first quarter to just $66 million.

Sales of the top performer in this space, Eli Lilly's Emgality, reached just $120 million in the first quarter. That means Biohaven's drug could take the top position before the end of the year. 

Current Biohaven shareholders probably want to hang on, but now may not be the best time to buy this soaring biotech stock. The company's market cap has soared to around $7.2 billion even though it lost a whopping $265 million in the first quarter. The combination of heavy losses and high expectations could lead to the market punishing the stock if Nurtec sales don't continue rocketing higher.