The Quit Big Tobacco campaign wants to put a chokehold on tobacco advertising by asking agencies, companies and universities to refuse to work with tobacco companies.

The campaign landed its first major corporate brand this week in CVS, which signed the pledge not to work with agencies that also work with tobacco and e-cigarette makers. CVS works with creative shops BBDO, Digitas and Matter; media firm UM; and PR agencies Cone and Kaplow.

The campaign is urging companies to refuse to work with agencies that partner with tobacco companies and encouraging marketing firms to quit the industry entirely. It also wants universities to refuse to take money from Big Tobacco and e-cigarette makers.

In 2014, CVS was the first pharmacy retailer to stop selling tobacco products in stores. Other major pharmacies like Walgreens and Rite-Aid continued to sell tobacco products, though Walgreens raised the minimum age to buy tobacco products to 21 this week.

More than 175 companies have signed Quit Big Tobacco’s pledge. The initiative was started by Vital Strategies, an organization focused on global health, last year. Other organizations that have signed on include Edelman, Truth Initiative, NCD Alliance and GMMB.

In March, CVS was also the first major pharmacy to start selling cannabidiol (CBD) products in stores, and the chain was followed by Walgreens and Rite-Aid.