After a tough and challenging 2016, pharma and biotech stocks have been showing signs of recovery this year. The sector started the year on a strong note with the Nasdaq Biotechnology Index and the NYSE ARCA Pharmaceutical Index gaining 10.7% and 5.7%, respectively, in the first quarter of 2017.

Despite the drug pricing issue remaining a headline risk this year, investors have been gaining confidence in the sector based on strong results, R&D success and innovation, FDA approvals, ramp up in new product sales and continued strong performance from legacy products. Expectations are also high that M&As will pick up this year.

There has also been some talk about speeding up the FDA approval process. Last year, the number of new drug approvals slipped to 22, well below the 45 approvals in 2015 and 41 in 2014. President Trump said that the FDA will be streamlined and the drug approval process will be much faster. The recently signed 21st Century Cures Act is a step in this direction. With the passing of this Act, expectations are that there will be more innovation in the sector and, maybe, a surge in new drug approvals. So far in 2017, 13 drugs have been approved by the agency.

While all these factors should work in favor of the sector, challenges remain in the form of additional competition, high-profile pipeline setbacks, a slowdown in the growth of mature products and loss of exclusivity for certain key drugs.

Here is a look at 3 of the best and worst-performing drug stocks in the first quarter of 2017.

3 Best Performing Drug Stocks in Q1

Esperion Therapeutics, Inc. (ESPR – Free Report): Ann Arbor, MI-based Esperion is a lipid management company focused on developing and commercializing convenient, complementary, cost-effective, once-daily, oral therapies for the treatment of patients with elevated low-density lipoprotein cholesterol (LDL-C). The company’s lead pipeline candidate, bempedoic acid, is in late-stage development with the company looking to file for FDA approval for a LDL-C lowering indication by the first half of 2019. Esperion’s shares gained a whopping 182% in the first quarter of 2017 — a key catalyst was news about the FDA confirming that the company’s ongoing LDL-C lowering program would be adequate to support approval for this indication. Top-line results from these studies should be out by mid-2018. Year-to-date (YTD), Esperion’s shares are up 185.2%, outperforming the Zacks-categorized Medical-Drugs industry, which is up 1.6%.