Uber shares surged 7.38% to close at $48.18 following news that a vaccine candidate is 90% effective at preventing COVID-19, and could start coming to market in a matter of months.

The announcement by drugmakers Pfizer and BioNTech sparked widespread optimism and helped boost shares across industries that have been weakened by the COVID-19 pandemic, including services like ride-hailing.

Uber’s share pop is notable beyond this one-day vaccine-news boost. This is the highest close for Uber since its public market debut in May 2019. This is also the first time since June 2019 that shares closed above its $45 IPO price.

Uber shares have been on an upswing over the past week in response to the passage of Proposition 22, a California ballot measure that allows companies to continue to classify gig workers as independent contractors. Uber, Lyft and other companies that rely on gig workers would have faced an expensive restructuring had voters rejected Prop 22.

Just days later, Uber reported its third-quarter earnings, results that revealed the disparate yet intertwining stories of its two core business segments. Uber’s ride-hailing business shrank, but made money, while its food delivery business expanded while continuing to lose money.

Uber didn’t meet investor expectations on revenue in the third quarter, which put some temporary downward pressure on shares. That drop proved to be short-lived as investors put more weight on the impact of the Prop 22 passage and today’s vaccine candidate news.