The economic impact of the coronavirus pandemic has started to weigh heavier on France’s largest drug company. On Wednesday, Sanofi announced net sales from April through June were about 3.5% lower than what it reported during the same period last year.

Most of the company’s units were in the red. Sales fell 7% for vaccines, 13% for general medicines and 8% for consumer health products as stay-in-place orders and general fear of the new virus kept patients away from pharmacies and doctors offices. Sanofi ultimately ended the second quarter with 8.2 billion euros, or roughly $9.6 billion, in net sales.

There was one bright spot, though. The company’s specialty care business grew more than 17%, mostly because of an anti-inflammation drug called Dupixent. First approved in the U.S. in 2017, Dupixent quickly became Sanofi’s top seller. Net sales of the drug reached 858 million euros for the most recent quarter, a 70% increase which may help Sanofi support its prediction that the brand will eventually deliver 10 billion euros in annual sales.

Yet Sanofi’s reliance on Dupixent also poses a problem for investors. If the product were to run into any serious obstacles, it would put a key source of revenue at risk. On an earnings call Wednesday, Credit Suisse analyst Jo Walton asked about U.S. drug pricing reform — the “elephant in the room” — and how recently announced executive orders could affect Dupixent.

Specifically, Walton homed in on one order about the so-called “international price index,” or IPI, a proposal that would place price limits on physician-administered drugs covered by Medicare Part B, based on how those drugs are priced in other countries. Dupixent, notably, is an injected drug administered both in doctors offices and at home.

Sanofi CEO Paul Hudson said the company is less exposed in the U.S. compared to its big pharma peers, and even less exposed when looking specifically at Medicare Part B.

“I think on IPI, it’s too convenient a headline. It’s a bit of a blunt instrument,” Hudson said, claiming that it’s not a “truthful comparison” to hold up a drug’s price in the U.S. to its price in another country, where it might be lower but also have worse patient access.

Part of the challenge for Sanofi, too, is that there aren’t many drugs to serve as backup growth drivers should Dupixent stumble. The company is working to build out its cancer drug business, but that will take time. And while some of its other new specialty drugs, such as Cablivi and Kevzara, have achieved double-digit growth, they still account for a relatively small amount of the company’s revenue.

Sanofi’s pipeline doesn’t have many near-term options either. Though the company has identified six experimental drugs that could bring meaningful additions to its business, the earliest of them won’t be submitted for approval until next year — meaning it might be in the mid-2020s before these drugs start to generate substantial sales.

After the challenging second quarter, Sanofi executives said they do expect some businesses to rebound in the back half of the year. Flu vaccines, for example, should perform better than they did in the third and fourth quarters last year, according to Thomas Triomphe, Sanofi’s head of vaccines.

Triomphe said health authorities selected the strain of flu to target earlier than in 2019, and that Sanofi last week started delivering doses to the U.S. In the third quarter of 2019, Sanofi recorded 735 million euros from net sales of flu vaccines, a nearly 30% decline that the company blamed on timing of delivery to the U.S.

Sanofi shares were up 2% in late morning trading Wednesday, to trade at almost $53 apiece on the Nasdaq stock exchange.