---
title: "News: Best-selling drug sales plummet, ZAI LAB's revenue declines"
type: "News"
locale: "en"
url: "https://longbridge.com/en/news/285675508.md"
description: "ZAI LAB Limited; due to a significant decline in sales of the best-selling drug \"Zellet,\" first-quarter revenue decreased by 6% year-on-year to USD 99.6 million, and net losses widened to USD 51 million. Sales of \"Zellet\" plummeted by 40% year-on-year to USD 30 million due to competition from generic drugs. Sales of the second-best-selling drug \"Weiqijia\" also declined, while sales of \"Zesida\" surged sevenfold. The company's stock price fell by 7.1% to HKD 15.5, with a cumulative increase of approximately 10.6% for the year"
datetime: "2026-05-08T06:45:43.000Z"
locales:
  - [zh-CN](https://longbridge.com/zh-CN/news/285675508.md)
  - [en](https://longbridge.com/en/news/285675508.md)
  - [zh-HK](https://longbridge.com/zh-HK/news/285675508.md)
---

# News: Best-selling drug sales plummet, ZAI LAB's revenue declines

The pharmaceutical research and development company **ZAI LAB Limited** (ZLB.US; 9688.HK) announced on Thursday that due to a significant decline in sales of its best-selling ovarian cancer drug "Zejula," first-quarter revenue fell 6% year-on-year to $99.6 million, compared to $107 million in the same period last year.

Due to competition from generic drugs, sales of "Zejula" plummeted 40% year-on-year to $30 million, down from $50 million in the same period last year. The company's second-best-selling drug "Vyvgart," used for the treatment of myasthenia gravis, also saw sales decrease from $18.1 million to $17.6 million. This decline was partially offset by a surge in revenue from the antibacterial pneumonia drug "Xacduro," which saw sales skyrocket sevenfold, rising from $1.1 million to $8.6 million.

The company's latest reported net loss was $51 million, slightly widening from a loss of $48.4 million in the same period last year.

During the Hong Kong trading session, ZAI LAB's stock price fell 7.1% to HKD 15.5. The stock has accumulated a rise of approximately 10.6% year-to-date.

_Yang Ge_

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