• April's consumer price index report is due out at 8:30 a.m. ET.
• Trump signed an executive order aiming to lower the cost of some prescription drugs.
• Coinbase will join the S&P 500, replacing Discover Financial Services.

Here are five key things investors need to know to start the trading day:

1. CPI watch

Investors' fears of a trade war — and a resulting recession — calmed on Monday after the U.S. and China agreed to drastically lower tariffs on each other's imports for 90 days. The Dow Jones Industrial Average closed up 1,160.72 points, or 2.81%, while the S&P 500 gained 3.26% and the Nasdaq Composite climbed 4.35%. Stock futures were lower before the bell Tuesday as traders braced for April's consumer price index report, due out at 8:30 a.m. ET. CPI is expected to remain at a 2.4% rate for the month on a year-over-year basis, according to the Dow Jones consensus. Follow live market updates.

2. Cure-all?

President Donald Trump on Monday signed an executive order aiming to lower the cost of some prescription drugs by tying their prices to significantly lower ones abroad. The effort, known as the "most favored nation" policy, directs Trump's trade and commerce officials to crack down on "unreasonable and discriminatory policies" in foreign countries. It also instructs the HHS secretary to establish a way for U.S. patients to bypass middlemen and buy drugs straight from manufacturers. But experts say it is unclear by how much the plan would reduce drug prices, which drugs it will affect, and whether it can be implemented at all. "The road ahead could be muddy," JPMorgan analysts wrote in a note.

3. Victory lap

The U.S. and China appear to have avoided an all-out trade war, at least for now, and both countries are declaring victory. Trump on Monday said China "agreed to open up" and suspend its trade barriers as part of the temporary tariff reduction deal, while Beijing cast the agreement as a vindication of its negotiating strategy. "China's firm countermeasures and resolute stance have been highly effective," one social media account linked to China's national broadcaster posted. Meanwhile, the Treasury Department reported a record $16.3 billion in customs duties in April as revenue from Trump's tariffs began to flow in. That's 86% more than the $8.75 billion collected in March and more than double the $7.1 billion in April 2024.

4. New home base

The S&P 500 just announced its newest member. Coinbase will join the benchmark index before trading on May 19, S&P Dow Jones Indices said Monday, causing shares of the cryptocurrency exchange to jump nearly 11% in extended trading. The move comes just days after Bitcoin jumped back above $100,000 for the first time since February. Since going public via a direct listing in 2021, Coinbase has been a volatile stock. It currently trades far below its 2021 peak and has underperformed Bitcoin so far this year, dropping 17% while the cryptocurrency is up 10%. Coinbase will replace Discover Financial Services, which is in the process of being acquired by Capital One Financial.

5. Stepping down

Shares of UnitedHealth Group dropped more than 10% before the bell Tuesday after the insurer suspended its 2025 guidance and announced that CEO Andrew Witty is stepping down for personal reasons. Stephen Hemsley, who previously served as UnitedHealth's CEO from 2006 to 2017, will take Witty's place, effective immediately. The company cited higher-than-expected medical costs as a reason for suspending its guidance. The announcement comes weeks after UnitedHealth reported its first quarterly earnings miss since 2008 and slashed its annual profit forecast.

— CNBC's Brian Evans, Fred Imbert, Yun Li, Annika Kim Constantino, Kevin Breuninger, Eunice Yoon, Erin Doherty, Jeff Cox, Ari Levy and Reuters contributed to this report.