FDA Accepts NDA of New F 18 Formulation for Prostate Cancer Imaging

The US FDA has accepted a New Drug Application (NDA) for a new formulation of piflufolastat F 18 (Pylarify), an advanced imaging agent used for PET scans in patients with prostate cancer.¹ This development marks a significant step forward in efforts to improve the accessibility and efficiency of prostate-specific membrane antigen (PSMA) PET imaging. The FDA has set a target action date of March 6, 2026, under the Prescription Drug User Fee Act.

This new formulation is designed to optimize the manufacturing process, with the potential to increase batch size by approximately 50%. This enhancement is expected to allow Lantheus Holdings, the sponsor, to serve a significantly larger number of patients and expand its geographic reach, addressing a critical need for accurate and timely prostate cancer diagnostics.

“We are pleased the FDA accepted Aphelion’s NDA for the new piflufolastat F 18 formulation, which we expect will improve patient access due to a significant increase in the number of doses per batch,” said Brian Markison, CEO of Lantheus, in a press release. “This formulation is a natural next step in our commitment to advancing PSMA imaging. There is a growing burden of prostate cancer in the U.S. and a clear need for accurate and early detection. Building on Pylarify’s proven performance and accuracy, Lantheus is well-positioned for continued leadership in prostate cancer imaging.”

The new formulation is anticipated to maintain the same high level of diagnostic performance as the existing piflufolastat F 18 product, which has demonstrated a median true-positive rate of 86% in a study of patients with recurrent prostate cancer based on rising prostate-specific antigen (PSA) levels.

Clinical Context and Diagnostic Performance

The FDA's acceptance of the NDA for this new piflufolastat F 18 formulation is a direct response to the growing burden of prostate cancer. In the US alone, prostate cancer is the second most frequently diagnosed cancer in men. According to estimates for 2025, there will be nearly 315,000 new cases and more than 35,000 deaths from the disease.² This new formulation aims to address the diagnostic challenges associated with this rising incidence by increasing patient access to PSMA PET imaging, a key diagnostic tool.¹

Piflufolastat F 18 is a fluorinated, small-molecule PSMA-targeted PET imaging agent. It is indicated for use in men with prostate cancer to detect PSMA-positive lesions. Its use is particularly critical in 2 key patient populations: those with suspected metastasis who are candidates for initial definitive therapy and those with suspected recurrence based on an elevated serum PSA level.

The agent's efficacy has been demonstrated in clinical settings, with studies showing its high diagnostic performance. The agent combines the accuracy of PET imaging with the precision of PSMA targeting and the clarity of an F 18 radioisotope, offering a comprehensive diagnostic picture for clinicians. Its widespread use, with over 500,000 scans performed in the US, underscores its established role in the prostate cancer diagnostic pathway.

Manufacturing and Access Advancements

The core innovation of this new formulation lies in its manufacturing process, which has been optimized to enhance production efficiency. By increasing the radioactive concentration and batch size, the new formulation can produce more doses per batch. This is a crucial logistical improvement for a radiopharmaceutical, which has a limited shelf life due to the decay of the radioactive isotope. The ability to produce more doses in a single batch allows for a more streamlined distribution network and reduces logistical barriers that can impede timely patient access, especially in geographically remote areas.

Important Safety Information and Clinical Considerations

While the new formulation promises enhanced accessibility, its safety profile is expected to be consistent with the existing piflufolastat F 18 agent. As with any diagnostic radiopharmaceutical, clinicians should be aware of important safety information. The agent has no contraindications, but there are warnings and precautions to consider.

Piflufolastat F 18 uptake is not exclusive to prostate cancer; it can also occur in other cancer types, nonmalignant processes, and normal tissues. Therefore, clinical correlation, including histopathological evaluation, is recommended to confirm findings. The diagnostic performance of the agent can also be influenced by serum PSA levels and risk factors like Gleason score and tumor stage.

While rare, hypersensitivity reactions can occur. Clinicians should monitor patients and have resuscitation equipment available.

Additionally, as a diagnostic radiopharmaceutical, piflufolastat F 18 exposes patients to radiation. Proper handling and administration procedures are essential to protect both patients and health care workers. Patients should be advised to hydrate and void frequently after administration to minimize radiation exposure.

The most frequently reported adverse reactions in clinical studies were headaches, dysgeusia, and fatigue, all occurring at a rate of 2% or less. The effect of androgen deprivation therapy and other androgen pathway-targeting treatments on the agent's performance has not been established.

Looking Ahead

The FDA's acceptance of the NDA for this new piflufolastat F 18 formulation marks a key milestone for Lantheus and the prostate cancer community. If approved, the new formulation has the potential to significantly enhance the clinical delivery of PSMA PET imaging, a crucial tool in the diagnosis and management of prostate cancer. The PDUFA date of March 6, 2026, will be a highly anticipated event for oncologists, radiologists, and patients alike, as it could pave the way for a new era of improved access to advanced diagnostic imaging.

REFERENCES:

1. Lantheus Announces FDA Acceptance of NDA for New Formulation for Market-Leading PSMA PET Imaging Agent. News release. Lantheus Holdings. August 6, 2025. Accessed August 7, 2025. https://tinyurl.com/4kd65jnm

2. Key Statistics for Prostate Cancer. American Cancer Society. Updated May 30, 2025. Accessed August 7, 2025. https://tinyurl.com/4u2spk9n