Shuttle Pharma FDA Orphan-Drug Nears Patient Enrollment Milestone for Phase 2 Clinical Trial

Rhea-AI Summary

Shuttle Pharmaceuticals (NASDAQ: SHPH) has reached nearly 50% enrollment in the initial randomized portion of its Phase 2 clinical trial for Ropidoxuridine, targeting glioblastoma treatment. The trial has shown promising initial results with the drug being well-tolerated and 84% of enrolled patients completing all seven cycles. The study involves 40 patients randomized into two dose levels (1,200 mg/day and 960 mg/day), with plans to add 14 more patients at the optimal dose. Ropidoxuridine, which has received FDA Orphan Drug Designation, is being developed as a radiation sensitizer for brain tumors. The trial is being conducted across six major medical centers, with final enrollment expected later this year and data readout in 2026. The company targets a significant market opportunity, with an estimated 400,000 US patients receiving radiation therapy for curative purposes annually, expected to grow by 22% over five years.

Positive

• Nearly 50% enrollment achieved in Phase 2 trial with favorable initial safety profile
• Drug well-tolerated with toxicity no greater than 2 on a 1-5 scale
• 84% of enrolled patients completed all seven treatment cycles
• FDA Orphan Drug Designation secured, providing potential marketing exclusivity
• Large market opportunity with 400,000 potential patients, expected to grow 22% in 5 years

Negative

• Final data readout not expected until 2026
• Additional patient enrollment still needed to reach statistical significance
• No guarantee of FDA approval or successful trial completion

Insights

Oncology Clinical Trials Expert

Shuttle Pharma's glioblastoma trial shows promising enrollment progress and preliminary safety, but efficacy data remains pending until 2026.

Shuttle Pharmaceuticals has reached a significant operational milestone in its Phase 2 trial of Ropidoxuridine for glioblastoma, approaching 50% enrollment in the dose-finding portion. The preliminary safety profile appears encouraging, with toxicity not exceeding grade 2 (on the standard 1-5 scale) and an impressive 84% completion rate for all seven treatment cycles among enrolled patients.

The trial's adaptive design intelligently evaluates two dose levels (960mg/day vs 1200mg/day) before expansion, representing a methodologically sound approach to optimize treatment. The ongoing analysis of pharmacokinetic/pharmacodynamic samples will provide valuable dose-response relationship data to inform future development.

Glioblastoma represents one of oncology's most formidable challenges, with standard therapy typically yielding median survival of only 12-15 months. The trial's multi-institutional approach across six major cancer centers strengthens its credibility and potential for generalizable results.

The FDA Orphan Drug Designation provides significant commercial advantages including potential marketing exclusivity upon approval, reflecting the significant unmet need in this indication.

While this enrollment progress demonstrates operational execution, the efficacy outcomes remain unknown until the anticipated data readout in 2026. The focus on survival as an endpoint is clinically appropriate, though specific targets for improvement over historical controls aren't detailed.

Radiation sensitizers represent a mechanistically rational approach to improving radiotherapy outcomes without necessarily increasing radiation dose. If successful, this approach could represent an important advancement for the estimated 400,000 US patients receiving curative-intent radiation therapy annually.

GAITHERSBURG, Md., May 08, 2025 (GLOBE NEWSWIRE) -- Shuttle Pharmaceuticals Holdings, Inc. (Nasdaq: SHPH) (“Shuttle Pharma” or the “Company”), a discovery and development stage specialty pharmaceutical company focused on improving outcomes for cancer patients treated with radiation therapy (RT), announced today that it has nearly achieved 50% enrollment in the initial randomized portion of its Phase 2 clinical trial of Ropidoxuridine for the treatment of patients with glioblastoma, with treatment sites reporting that the drug has been well tolerated and toxicity no greater than 2 on a scale of 1-5. Further, 84% of the enrolled patients have completed all seven cycles. Shuttle has begun analyzing pharmacokinetic/pharmacodynamic samples to compare the relationship between dose and response in terms of the extent and duration of Ropidoxuridine’s action. Our objective is to finalize enrollment later this year with follow up and data read out in 2026.

“We are incredibly encouraged by the expedited progress of our Phase 2 trial and the dedication of our team, clinical partners, and patients who are making this milestone possible,” commented Shuttle Pharma's Chairman and Chief Scientific Officer, Anatoly Dritschilo, M.D. “If approved, we believe that Ropidoxuridine has the potential to redefine the standard approach for how to care for patients with glioblastoma.”

Ropidoxuridine (IPdR) is Shuttle Pharma's lead candidate radiation sensitizer for use in combination with RT to treat brain tumors (glioblastoma), a deadly malignancy of the brain with no known cure. Shuttle Pharma previously received Orphan Drug Designation from the FDA, providing Shuttle Pharma with potential marketing exclusivity upon obtaining FDA approval for treatment of this disease.

The Phase 2 clinical trial design initially randomizes 40 patients into two different dose levels of drug, with 20 patients receiving 1,200 mg/day and 20 patients receiving 960 mg/day, to determine an optimal dose for use in glioblastoma patients in combination with RT. After the optimal dose is identified, 14 additional patients will be enrolled at the optimal dose to reach statistical significance with the end-point demonstrating increased survival as compared to historical controls.

The Phase 2 clinical trial is conducted at Georgetown University Medical Center, Allegheny Health Network (AHN) Cancer Institute, UNC Medical Center, the UVA Cancer Center, John Theurer Cancer Center at Hackensack University Medical Center, and Miami Cancer Institute, part of Baptist Health South Florida.

“This clinical trial is critical to the broader radiation therapy industry as we look to leverage radiation sensitizers to increase cancer cure rates, prolong patient survival and improve quality of life for patients suffering from glioblastoma. I look forward to continued trial execution as we aim to improve the lives of millions of patients impacted by cancer and to bring hope to patients and families around the world,” Dr. Dritschilo concluded.

An estimated 800,000 patients in the US are treated with radiation therapy for their cancers yearly. According to the American Cancer Society and the American Society of Radiation Oncologists, about 50% are treated for curative purposes and the balance for palliative therapeutic care. The market opportunity for radiation sensitizers lies with the 400,000 patients treated for curative purposes, with this number expected to grow by more than 22% over the next five years.

More information about the Phase 2 study (NCT06359379) can be found at www.clinicaltrials.gov.

About Shuttle Pharmaceuticals

Founded in 2012 by faculty members of the Georgetown University Medical Center, Shuttle Pharma is a discovery and development stage specialty pharmaceutical company focused on improving the outcomes for cancer patients treated with radiation therapy (RT). Our mission is to improve the lives of cancer patients by developing therapies that are designed to maximize the effectiveness of RT while limiting the side effects of radiation in cancer treatment. Although RT is a proven modality for treating cancers, by developing radiation sensitizers, we aim to increase cancer cure rates, prolong patient survival and improve quality of life when used as a primary treatment or in combination with surgery, chemotherapy and immunotherapy. For more information, please visit our website at www.shuttlepharma.com.

Safe Harbor Statement

Statements in this press release about future expectations, plans and prospects, as well as any other statements regarding matters that are not historical facts, may constitute “forward-looking statements.” These statements include, but are not limited to, statements concerning the development of our company. The words “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “target,” “will,” “would” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. Actual results may differ materially from those indicated by such forward-looking statements as a result of various important factors, including factors discussed in the “Risk Factors” section of Shuttle Pharma’s Annual Report on Form 10-K for the year ended December 31, 2024, filed with the SEC on February 26, 2025, as well other SEC filings. Any forward-looking statements contained in this press release speak only as of the date hereof and, except as required by federal securities laws, Shuttle Pharmaceuticals specifically disclaims any obligation to update any forward-looking statement, whether as a result of new information, future events or otherwise.

Shuttle Pharmaceuticals
Anatoly Dritschilo, M.D.
Chairman and Chief Scientific Officer
240-403-4212
info@shuttlepharma.com

Investor Contacts
Lytham Partners, LLC
Robert Blum
602-889-9700
shph@lythampartners.com 

FAQ

What is the current status of SHPH's Phase 2 clinical trial for Ropidoxuridine?

The trial has reached nearly 50% enrollment in its initial randomized portion, with the drug being well-tolerated and 84% of enrolled patients completing all seven cycles. Final enrollment is expected later in 2025, with data readout in 2026.

What is the market potential for Shuttle Pharma's Ropidoxuridine?

The market includes approximately 400,000 US patients receiving radiation therapy for curative purposes annually, with 22% expected growth over five years. The drug has FDA Orphan Drug Designation for glioblastoma treatment.

How many patients are involved in SHPH's Phase 2 clinical trial?

The trial design includes 40 initial patients randomized into two dose levels (1,200 mg/day and 960 mg/day), with plans to add 14 more patients at the optimal dose to reach statistical significance.

Which medical centers are conducting Shuttle Pharma's Phase 2 trial?

The trial is being conducted at six centers: Georgetown University Medical Center, Allegheny Health Network Cancer Institute, UNC Medical Center, UVA Cancer Center, John Theurer Cancer Center, and Miami Cancer Institute.

What is the purpose of Ropidoxuridine in cancer treatment?

Ropidoxuridine is being developed as a radiation sensitizer to improve outcomes for patients with glioblastoma (brain tumors) when used in combination with radiation therapy, aiming to increase cancer cure rates and prolong survival.