---
type: "Topics"
locale: "en"
url: "https://longbridge.com/en/topics/42100313.md"
description: "$Regencell Bioscience(RGC.US) dropped -12% in a single day. This small-cap stock, which had previously surged, is right at the deadline for a class-action lawsuit. The legal uncertainty has scared off earlier speculative positions. $Tempus AI(TEM.US) and $Moderna(MRNA.US) both fell six to seven percentage points. AI diagnostics and vaccines each have their own pressures. $Pfizer(PFE.US) was basically flat, and $Recursion Pharmaceuticals(RXRX.US) dipped slightly. Today, in the biopharma sector, large pharma companies, AI drug discovery, and speculative small-caps had three completely different fates 😔. This kind of micro-cap stock, which relies purely on themes, experiences extreme volatility when news reverses. Without fundamental support, it really can't withstand a fall."
datetime: "2026-06-23T09:41:24.000Z"
locales:
  - [en](https://longbridge.com/en/topics/42100313.md)
  - [zh-CN](https://longbridge.com/zh-CN/topics/42100313.md)
  - [zh-HK](https://longbridge.com/zh-HK/topics/42100313.md)
author: "[Dimoo](https://longbridge.com/en/profiles/26968366.md)"
---

# $Regencell Bioscience(RGC.US) dropped -12% in a si…


### Related Stocks

- [MRNA.US](https://longbridge.com/en/quote/MRNA.US.md)
- [PFE.US](https://longbridge.com/en/quote/PFE.US.md)
- [RXRX.US](https://longbridge.com/en/quote/RXRX.US.md)
- [RGC.US](https://longbridge.com/en/quote/RGC.US.md)
- [TEM.US](https://longbridge.com/en/quote/TEM.US.md)