Monday was a good day for the stock market, as investors seemed optimistic on a broad range of topics. Enthusiasm about cooling tensions on the global trade front pointed the way toward a more favorable outcome, and third-quarter earnings have generally been strong thus far. A few stocks managed to post extremely strong gains on good news. PetMed Express (NASDAQ:PETS), Seattle Genetics (NASDAQ:SGEN), and Coty (NYSE:COTY) were among the top performers. Here's why they did so well.

PetMed holds up

Shares of PetMed Express soared 34% after the online veterinary pharmacy company reported its fiscal second-quarter results. On their face, PetMed's numbers didn't seem all that healthy, as revenue sank 2% compared to the year-ago figure and net income was down by 38% over the same period. Yet the company's key metrics didn't decline as much as some had feared, and encouraging gains in reorders and a sizable boost to margins helped stoke confidence in PetMed's future. With investors having gotten used to poor past performance, PetMed's latest results were a welcome surprise.

Dog in a bicycle trailer.

Image source: PetMed Express.

Seattle Genetics gets promising test results

Seattle Genetics saw its stock jump more than 15% following the release of favorable results from its phase 2 trial of its late-stage breast cancer treatment tucatinib. The trial met its primary endpoint of demonstrating significant increases in progression-free survival for patients using tucatinib in combination with two other cancer treatments compared to using those two treatments alone. Tucatinib also met the study's secondary endpoints and showed a reasonable safety profile. With plans to submit a new drug application to the U.S. Food and Drug Administration in early 2020, Seattle Genetics has investors excited about what the future could bring for the biotech company.

Coty looks at its options

Finally, shares of Coty climbed 13%. The beauty company said that it's looking at exploring strategic alternatives for various parts of its business, including its professional beauty segment and hair-products brands, as well as its Brazilian operations. Those alternatives could include selling off those parts of Coty's business, with the idea of using any proceeds to reduce debt. The company believes that it will have to focus on its fragrance, cosmetics, and skin care businesses in order to execute a turnaround, and divesting noncore assets would help it do that. It'll be interesting to see what interest Coty's assets get, but investors are optimistic that the beauty specialist is moving in the right direction.