Unicycive's Kidney Drug OLC Back on FDA Track After Manufacturing Fix

By George Millen

LOS ALTOS, CA – December 29, 2025 – Unicycive Therapeutics has resubmitted its New Drug Application (NDA) to the U.S. Food and Drug Administration (FDA) for oxylanthanum carbonate (OLC), marking a significant step forward for the company and potentially for hundreds of thousands of patients with chronic kidney disease (CKD). The move signals a pivotal comeback after a regulatory setback earlier in the year and places the novel treatment for hyperphosphatemia back on a path toward a potential 2026 approval.

The investigational drug is designed as an oral phosphate binder for patients on dialysis, a group that struggles with dangerously high phosphate levels. The resubmission follows a period of intense focus on resolving a manufacturing compliance issue that had previously halted the drug's progress at the FDA.

Overcoming a Critical Regulatory Hurdle

Unicycive's journey hit a significant roadblock in June 2025 when it received a Complete Response Letter (CRL) from the FDA. A CRL indicates that the agency cannot approve the application in its present form. However, the deficiency was not related to the drug's clinical data, safety, or efficacy. Instead, the FDA cited a single issue: the compliance status of a third-party manufacturing vendor responsible for a part of the production process.

In the months that followed, Unicycive worked closely with the vendor to rectify the situation. In a key September 2025 Type A meeting, the FDA provided feedback and confirmed that resolving the vendor's compliance status was the sole remaining hurdle. The subsequent progress made by the manufacturer was deemed sufficient to move forward.

“Our original third-party manufacturing vendor has made significant progress toward regaining FDA compliance, allowing us to resubmit the OLC NDA as planned,” said Shalabh Gupta, M.D., Chief Executive Officer of Unicycive, in a statement. “With a cash runway into 2027, we are well-positioned to complete the regulatory approval process for OLC so we can prepare to bring this important treatment option to dialysis patients with hyperphosphatemia as soon as possible.”

Adding another layer of confidence, European Union regulatory authorities inspected the same manufacturing facility after the FDA had issued its CRL and identified no deficiencies. This divergence in findings suggests the issues may have been specific to FDA requirements or were swiftly addressed. With the resubmission now filed, Unicycive anticipates the FDA will acknowledge its acceptance for review within 30 days and complete its review within six months, setting a potential target action date in mid-2026.

A New Hope for Dialysis Patients

For the more than 450,000 individuals in the U.S. on dialysis, hyperphosphatemia is a near-universal and relentless complication. The condition, characterized by an inability to clear excess phosphate from the blood, is strongly linked to increased rates of hospitalization and death, primarily from cardiovascular events. Managing it requires strict dietary restrictions and a daily regimen of phosphate-binding drugs taken with every meal.

The challenge, however, lies in patient adherence. Current treatments often involve a significant pill burden, with some patients required to take as many as 12 large pills per day. This daunting regimen contributes to widespread non-adherence, with studies showing that approximately 75% of dialysis patients in the U.S. fail to achieve the recommended target phosphorus levels.

This is the clinical need Unicycive aims to address with OLC. The drug leverages proprietary nanoparticle technology to deliver high phosphate-binding potency in a much smaller form factor. Recent data presented at the American Society of Nephrology (ASN) Kidney Week 2025 highlighted OLC's potential, demonstrating a significant reduction in pill burden compared to currently available binders—a seven-fold reduction in pill volume and a two-fold reduction in pill count.

Unlike its reference drug, Fosrenol, which is a chewable tablet, OLC is designed to be a smaller, easy-to-swallow pill. By drastically reducing the number and size of pills, Unicycive believes OLC can meaningfully improve patient adherence, leading to better phosphate control and, ultimately, improved health outcomes and quality of life.

Strategic Positioning in a Competitive Market

The resubmission not only de-risks the regulatory path for OLC but also sharpens Unicycive's strategic position in the competitive kidney disease market. The company is seeking approval via the 505(b)(2) regulatory pathway, a streamlined process that allows it to rely on the FDA's previous findings of safety and effectiveness for an already approved drug, in this case, lanthanum carbonate.

If approved, OLC will enter a market with established players like Sanofi's Renvela (sevelamer carbonate) and Vifor Pharma's Velphoro (sucroferric oxyhydroxide). However, its 'best-in-class' profile centered on a lower pill burden provides a clear and compelling differentiator that could drive rapid adoption among both patients and nephrologists.

Investor confidence appears to be on the rise. Following the announcement, analysts at Guggenheim reiterated a Buy rating with a $46 price target, and H.C. Wainwright raised its target to $22. This optimism is bolstered by the company's solid financial footing. Unicycive reported having $42 million in cash as of September 30, 2025, providing a runway that it states extends into 2027—more than enough to see OLC through the approval process and into its initial commercial launch.

The company has also shored up its corporate health, regaining compliance with Nasdaq's minimum bid price requirement in July 2025 after a reverse stock split. Protecting its lead asset, Unicycive has secured a strong global patent portfolio for OLC, with composition of matter patents providing exclusivity until 2031 and the potential for a term extension until 2035. This long-term protection is crucial for realizing the drug's full commercial potential in a market desperate for innovation.