REGENXBIO's RGX-121 Application Rejected by FDA
Written by Emily J. Thompson, Senior Investment Analyst
Updated: 5 days ago
0mins
Should l Buy RGNX?
Source: NASDAQ.COM
- FDA Complete Response Letter: REGENXBIO announced that its Biologics License Application (BLA) for RGX-121 received a Complete Response Letter from the FDA, which, while agreeing with the study protocol in principle, identified several issues that hinder approval, indicating significant regulatory challenges for the therapy.
- Clinical Trial Concerns: The FDA raised concerns regarding the eligibility criteria for the patient population, the comparability of the natural-history control group, and the suitability of CSF HS D2S6 as a surrogate endpoint, which could impact predictions of RGX-121's clinical benefits and delay its market entry.
- Next Steps: REGENXBIO plans to request a Type A meeting with the FDA to discuss the CRL and its strategy for resubmitting the BLA, aiming to clarify the neuronopathic patient population with additional evidence from global MPS II experts and supplement the application with long-term clinical data to enhance its validity.
- Market Reaction: Following the announcement, RGNX's stock closed at $10.31, down 0.19%, and further declined to $9.01 in pre-market trading, reflecting a 12.61% drop, indicating market pessimism regarding the future of this therapy.
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Analyst Views on RGNX
Wall Street analysts forecast RGNX stock price to rise
7 Analyst Rating
7 Buy
0 Hold
0 Sell
Strong Buy
Current: 8.350
Low
19.00
Averages
29.71
High
45.00
Current: 8.350
Low
19.00
Averages
29.71
High
45.00
About RGNX
REGENXBIO Inc. is a clinical-stage biotechnology company seeking to improve lives through the curative potential of gene therapy. The Company has developed a pipeline of gene therapy programs using its proprietary adeno-associated virus (AAV) gene therapy delivery platform (NAV Technology Platform) to address genetic diseases. It is focused on its internal development pipeline in three areas: retinal, neuromuscular, and neurodegenerative diseases. Its investigational AAV therapeutics include ABBV-RGX-314, RGX-202, RGX-121, and RGX-111. It is developing ABBV-RGX-314 in collaboration with AbbVie to treat large patient populations impacted by wet age-related macular degeneration, diabetic retinopathy (DR) and other chronic retinal diseases characterized by loss of vision. It is developing RGX-202 to treat Duchenne muscular dystrophy (Duchenne). The Company is developing RGX-121 to treat Mucopolysaccharidosis type II (MPS II), a progressive, neurodegenerative lysosomal storage disorder.
About the author
Emily J. Thompson
Emily J. Thompson, a Chartered Financial Analyst (CFA) with 12 years in investment research, graduated with honors from the Wharton School. Specializing in industrial and technology stocks, she provides in-depth analysis for Intellectia’s earnings and market brief reports.
REGENXBIO Faces Class Action Lawsuit
- Class Action Initiated: REGENXBIO Inc. is facing a class action lawsuit led by Andre Kuik for allegedly providing false information to investors, covering securities transactions from February 9, 2022, to January 27, 2026, which could further damage the company's reputation and stock price.
- FDA Clinical Hold: On January 28, 2026, REGENXBIO announced that the FDA placed a clinical hold on its gene therapy RGX-111 due to the discovery of an intraventricular tumor in a trial participant, causing the stock price to plummet 17.8% in a single day from $13.41 to $11.01, indicating a severe loss of investor confidence in the company's future.
- Investor Loss Compensation: The law firm Levi & Korsinsky stated it would seek compensation for investors who suffered losses due to corporate misrepresentations, urging RGNX shareholders to apply as lead plaintiffs before the April 14, 2026 deadline, highlighting the potential financial implications of the legal action on the company.
- Law Firm's Credentials: Over the past 20 years, Levi & Korsinsky has secured hundreds of millions for aggrieved shareholders and has extensive experience in complex securities litigation, being ranked among the top securities litigation firms in the U.S. for seven consecutive years, showcasing its strength and influence in such cases.
See More
Biotech Sector Faces FDA Turmoil
- FDA Chaos Impacts Approvals: The biotech sector had a strong performance in 2025, with the XBI index outperforming NVIDIA, yet ongoing chaos at the FDA may lead to longer drug approval cycles, increasing investment risks and affecting industry confidence.
- Executive Warns of Industry Risks: Former FDA oncology head Richard Pasdur warned at the JP Morgan conference that the breach between political appointees and drug reviewers could lead to inconsistent approval standards, creating uncertainty for biotech companies.
- Gene Therapy Approval Delays: Regenxbio's expected approval for a Hunter syndrome drug on February 8 is now unlikely due to a tumor found in a patient during clinical trials, indicating stricter FDA oversight on gene therapies and prompting investor caution.
- Twist Bioscience Shows Recovery: Twist Bioscience reported $104 million in revenue for Q1, despite remaining unprofitable, but reduced cash burn indicates a sustainable growth trend, attracting investor interest amid the biotech downturn.
See More
REGENXBIO Faces FDA Challenges for Gene Therapy Approval
- FDA Response Letter Issued: REGENXBIO's shares fell after receiving a response letter from the FDA regarding its Hunter syndrome gene therapy, indicating regulatory concerns about trial design that could delay the approval timeline.
- Trial Design Concerns: The FDA's questioning of the trial design may impact the efficacy assessment of the therapy, negatively affecting REGENXBIO's market outlook and increasing uncertainty for investors.
- Approval Timeline Delayed: Due to the FDA's feedback, REGENXBIO may need to reevaluate its clinical trial plans, which will push back the originally scheduled approval timeline and affect the company's future revenue expectations.
- Negative Market Reaction: The stock price decline following the FDA's response letter reflects market concerns about REGENXBIO's future direction, potentially leading to decreased investor confidence and impacting its ability to raise funds.
See More
REGENXBIO's RGX-121 BLA Accepted by FDA Under Accelerated Approval Pathway
- FDA Approval Update: The FDA has accepted REGENXBIO's RGX-121 BLA under the accelerated approval pathway; however, the PDUFA goal date has been extended from November 9, 2025, to February 8, 2026, indicating the agency's cautious approach to expedited approvals.
- Reasons for CRL: The FDA issued a Complete Response Letter (CRL) for RGX-121, citing concerns regarding study eligibility criteria and the appropriateness of a surrogate endpoint, suggesting that new studies and long-term follow-ups may be necessary, which poses challenges in an ultra-rare disease population.
- Market Reaction: Despite regulatory hurdles, REGENXBIO's stock shows strong momentum in the market, with analysts maintaining a
See More
REGENXBIO's RGX-121 Application Rejected by FDA
- FDA Complete Response Letter: REGENXBIO announced that its Biologics License Application (BLA) for RGX-121 received a Complete Response Letter from the FDA, which, while agreeing with the study protocol in principle, identified several issues that hinder approval, indicating significant regulatory challenges for the therapy.
- Clinical Trial Concerns: The FDA raised concerns regarding the eligibility criteria for the patient population, the comparability of the natural-history control group, and the suitability of CSF HS D2S6 as a surrogate endpoint, which could impact predictions of RGX-121's clinical benefits and delay its market entry.
- Next Steps: REGENXBIO plans to request a Type A meeting with the FDA to discuss the CRL and its strategy for resubmitting the BLA, aiming to clarify the neuronopathic patient population with additional evidence from global MPS II experts and supplement the application with long-term clinical data to enhance its validity.
- Market Reaction: Following the announcement, RGNX's stock closed at $10.31, down 0.19%, and further declined to $9.01 in pre-market trading, reflecting a 12.61% drop, indicating market pessimism regarding the future of this therapy.
See More
Regenxbio's Gene Therapy Faces FDA Rejection
- FDA Response Letter Issued: The U.S. FDA issued a complete response letter rejecting Regenxbio's biologics license application for its gene therapy RGX-121, resulting in a 15% drop in premarket trading for the company.
- Clinical Trial Uncertainties: The FDA highlighted significant issues, including the inability to adequately define eligibility criteria for patients with neuronopathic disease and the comparability of the external control group, which were key reasons for the rejection.
- Future Path Planning: Despite the challenges, Regenxbio intends to collaborate with the FDA to explore options for resubmitting the application, which may involve new studies, treating additional patients, and conducting longer-term follow-ups.
- Ultra-Rare Disease Challenges: As MPS II is classified as an ultra-rare disease, the multiple potential paths suggested by the FDA pose significant implementation challenges, particularly given the limited patient population, increasing uncertainty for the company's future prospects.
See More
REGENXBIO Faces Class Action Lawsuit
- Class Action Initiated: REGENXBIO Inc. is facing a class action lawsuit led by Andre Kuik for allegedly providing false information to investors, covering securities transactions from February 9, 2022, to January 27, 2026, which could further damage the company's reputation and stock price.
- FDA Clinical Hold: On January 28, 2026, REGENXBIO announced that the FDA placed a clinical hold on its gene therapy RGX-111 due to the discovery of an intraventricular tumor in a trial participant, causing the stock price to plummet 17.8% in a single day from $13.41 to $11.01, indicating a severe loss of investor confidence in the company's future.
- Investor Loss Compensation: The law firm Levi & Korsinsky stated it would seek compensation for investors who suffered losses due to corporate misrepresentations, urging RGNX shareholders to apply as lead plaintiffs before the April 14, 2026 deadline, highlighting the potential financial implications of the legal action on the company.
- Law Firm's Credentials: Over the past 20 years, Levi & Korsinsky has secured hundreds of millions for aggrieved shareholders and has extensive experience in complex securities litigation, being ranked among the top securities litigation firms in the U.S. for seven consecutive years, showcasing its strength and influence in such cases.
See More
Biotech Sector Faces FDA Turmoil
- FDA Chaos Impacts Approvals: The biotech sector had a strong performance in 2025, with the XBI index outperforming NVIDIA, yet ongoing chaos at the FDA may lead to longer drug approval cycles, increasing investment risks and affecting industry confidence.
- Executive Warns of Industry Risks: Former FDA oncology head Richard Pasdur warned at the JP Morgan conference that the breach between political appointees and drug reviewers could lead to inconsistent approval standards, creating uncertainty for biotech companies.
- Gene Therapy Approval Delays: Regenxbio's expected approval for a Hunter syndrome drug on February 8 is now unlikely due to a tumor found in a patient during clinical trials, indicating stricter FDA oversight on gene therapies and prompting investor caution.
- Twist Bioscience Shows Recovery: Twist Bioscience reported $104 million in revenue for Q1, despite remaining unprofitable, but reduced cash burn indicates a sustainable growth trend, attracting investor interest amid the biotech downturn.
See More
REGENXBIO Faces FDA Challenges for Gene Therapy Approval
- FDA Response Letter Issued: REGENXBIO's shares fell after receiving a response letter from the FDA regarding its Hunter syndrome gene therapy, indicating regulatory concerns about trial design that could delay the approval timeline.
- Trial Design Concerns: The FDA's questioning of the trial design may impact the efficacy assessment of the therapy, negatively affecting REGENXBIO's market outlook and increasing uncertainty for investors.
- Approval Timeline Delayed: Due to the FDA's feedback, REGENXBIO may need to reevaluate its clinical trial plans, which will push back the originally scheduled approval timeline and affect the company's future revenue expectations.
- Negative Market Reaction: The stock price decline following the FDA's response letter reflects market concerns about REGENXBIO's future direction, potentially leading to decreased investor confidence and impacting its ability to raise funds.
See More
REGENXBIO's RGX-121 BLA Accepted by FDA Under Accelerated Approval Pathway
- FDA Approval Update: The FDA has accepted REGENXBIO's RGX-121 BLA under the accelerated approval pathway; however, the PDUFA goal date has been extended from November 9, 2025, to February 8, 2026, indicating the agency's cautious approach to expedited approvals.
- Reasons for CRL: The FDA issued a Complete Response Letter (CRL) for RGX-121, citing concerns regarding study eligibility criteria and the appropriateness of a surrogate endpoint, suggesting that new studies and long-term follow-ups may be necessary, which poses challenges in an ultra-rare disease population.
- Market Reaction: Despite regulatory hurdles, REGENXBIO's stock shows strong momentum in the market, with analysts maintaining a
See More
REGENXBIO's RGX-121 Application Rejected by FDA
- FDA Complete Response Letter: REGENXBIO announced that its Biologics License Application (BLA) for RGX-121 received a Complete Response Letter from the FDA, which, while agreeing with the study protocol in principle, identified several issues that hinder approval, indicating significant regulatory challenges for the therapy.
- Clinical Trial Concerns: The FDA raised concerns regarding the eligibility criteria for the patient population, the comparability of the natural-history control group, and the suitability of CSF HS D2S6 as a surrogate endpoint, which could impact predictions of RGX-121's clinical benefits and delay its market entry.
- Next Steps: REGENXBIO plans to request a Type A meeting with the FDA to discuss the CRL and its strategy for resubmitting the BLA, aiming to clarify the neuronopathic patient population with additional evidence from global MPS II experts and supplement the application with long-term clinical data to enhance its validity.
- Market Reaction: Following the announcement, RGNX's stock closed at $10.31, down 0.19%, and further declined to $9.01 in pre-market trading, reflecting a 12.61% drop, indicating market pessimism regarding the future of this therapy.
See More
Regenxbio's Gene Therapy Faces FDA Rejection
- FDA Response Letter Issued: The U.S. FDA issued a complete response letter rejecting Regenxbio's biologics license application for its gene therapy RGX-121, resulting in a 15% drop in premarket trading for the company.
- Clinical Trial Uncertainties: The FDA highlighted significant issues, including the inability to adequately define eligibility criteria for patients with neuronopathic disease and the comparability of the external control group, which were key reasons for the rejection.
- Future Path Planning: Despite the challenges, Regenxbio intends to collaborate with the FDA to explore options for resubmitting the application, which may involve new studies, treating additional patients, and conducting longer-term follow-ups.
- Ultra-Rare Disease Challenges: As MPS II is classified as an ultra-rare disease, the multiple potential paths suggested by the FDA pose significant implementation challenges, particularly given the limited patient population, increasing uncertainty for the company's future prospects.
See More
