RCKT Stock Tanks on Patient Death in Danon Disease Study

Shares of Rocket Pharmaceuticals RCKT plunged 62.8% on Tuesday after the company announced a patient death in a pivotal phase II study evaluating its investigational gene therapy candidate, RP-A501, for treating patients with Danon disease.

The company confirmed that one of the patients in the study experienced an acute systemic infection, an unexpected serious adverse event, which resulted in his untimely death.

Following the turn of events, RCKT has voluntarily paused further dosing in the study evaluating RP-A501 in Danon disease. Last week, the FDA placed a clinical hold on the study.

The company is currently carrying out a comprehensive root cause analysis to identify the reason for such an adverse event.

RCKT is working with the FDA, the Independent Data Safety Monitoring Committee, clinical investigators and scientific experts to restart the study as soon as possible, while ensuring the safety of all the patients in the study.

Per management, RP-A501 is the first gene therapy to demonstrate safety and efficacy in clinical studies for a cardiovascular condition.

RCKT's Stock Performance

Year to date, shares of Rocket Pharmaceuticals have plunged 81.5% compared with the industry’s decline of 5.8%.

RCKT's Recent Pipeline Setbacks

Setbacks related to pipeline candidates have been a major concern for Rocket Pharmaceuticals in recent times.

The company is developing Kresladi to treat patients with severe leukocyte adhesion deficiency-I (LAD-I), a rare genetic disorder.

Last June, the FDA issued a complete response letter (CRL) to the biologics license application (BLA) seeking approval for Kresladi to treat LAD-I.

Per the CRL, the FDA sought "limited" additional information on the Chemistry Manufacturing and Controls (CMC), which is part of the BLA submission. The regulatory body is currently reviewing the limited additional CMC information for Kresladi.

This was the second time that the FDA had requested additional information from the company on Kresladi’s CMC. In February 2024, the FDA extended the review period of the Kresladi BLA by an additional three months.

The company is planning to file a complete BLA to resolve the CRL later in 2025.

RCKT's Zacks Rank & Stocks to Consider

Rocket Pharmaceuticals currently carries a Zacks Rank #3 (Hold).

Some better-ranked stocks in the biotech sector are Lexicon Pharmaceuticals LXRX, Chemomab Therapeutics CMMB and Amarin AMRN, each carrying a Zacks Rank #2 (Buy) at present. You can see the complete list of today’s Zacks #1 Rank (Strong Buy) stocks here.

In the past 60 days, estimates for Lexicon’s loss per share have narrowed from 37 cents to 32 cents for 2025. During the same time, loss per share estimates for 2026 have narrowed from 35 cents to 31 cents. Year to date, shares of LXRX have lost 6.6%.

LXRX’s earnings beat estimates in three of the trailing four quarters and missed the same on the remaining occasion, delivering an average surprise of 11.97%.

In the past 60 days, estimates for Chemomab Therapeutics’ loss per share have narrowed from 70 cents to 60 cents for 2025. During the same time, loss per share estimates for 2026 have narrowed from 80 cents to 70 cents. Year to date, shares of CMMB have declined 22.7%.

CMMB’s earnings beat estimates in two of the trailing four quarters, matched once and missed the same on the remaining occasion, delivering an average surprise of 5.00%.

In the past 60 days, estimates for Amarin’s loss per share have narrowed from $5.33 to $3.48 for 2025. During the same time, loss per share estimates for 2026 have narrowed from $4.13 to $2.67. Year to date, shares of AMRN have gained 17.1%.

AMRN’s earnings beat estimates in two of the trailing four quarters, matched once and missed the same on the remaining occasion, delivering an average surprise of 29.11%.

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This article originally published on Zacks Investment Research (zacks.com).

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