PridCor's Long COVID Therapy Gains Key FDA Exemption and Peer Validation

TUSCALOOSA, Ala. – January 06, 2026 – In a significant development for the millions suffering from Long COVID, PridCor Therapeutics announced today that its planned clinical trial has cleared two critical hurdles, receiving both scientific validation in a peer-reviewed journal and a key regulatory exemption from the U.S. Food and Drug Administration (FDA). The milestones are set to accelerate the SHIELD Study, a Phase 2 trial for the company’s combination antiviral regimen, offering a tangible sign of progress in the urgent search for effective treatments for the debilitating condition.

The Tuscaloosa-based biopharmaceutical firm, which focuses on infection-associated chronic illnesses, is now positioned to efficiently advance its lead therapy into a randomized, double-blind, placebo-controlled study in the first quarter of 2026. This next phase will be conducted in collaboration with a team of world-renowned Long COVID experts at the Icahn School of Medicine at Mount Sinai.

Scientific Rationale Solidified

The foundation for PridCor's upcoming trial was substantially strengthened by the publication of a clinical case series in Frontiers in Immunology, a respected, high-impact journal. The paper, titled “Patient-reported improvements from use of IMC-2 alone and IMC-2 and Paxlovid® in a Long COVID cohort: a case series,” details compelling outcomes from a small, open-label study involving 24 patients.

Researchers observed substantial improvements in some of the most common and life-altering Long COVID symptoms, including profound fatigue, cognitive impairment or “brain fog,” and dysautonomia—a malfunction of the autonomic nervous system. The study evaluated two regimens: IMC-2 (a combination of the antiviral valacyclovir and the anti-inflammatory celecoxib) and a combination of IMC-2 with a 15-day course of Paxlovid.

Notably, patients receiving the combination of IMC-2 and Paxlovid reported a statistically significant greater reduction in fatigue compared to those on IMC-2 alone (p < 0.0001). The durability of these improvements was a standout feature, with patient follow-up extending as long as 731 days—providing rare long-term data in a field where many treatments offer only transient relief. The authors noted that the symptom improvements remained consistent at follow-ups of 120, 305, and 731 days.

While the authors acknowledged the study's limitations, including its small size and open-label design, the findings provide a robust scientific rationale for the larger, more rigorous SHIELD Study. This publication moves the therapy beyond anecdotal reports into the realm of formal scientific scrutiny.

An Accelerated Regulatory Pathway

In parallel with its scientific validation, PridCor received confirmation from the FDA that its upcoming trial qualifies for an Investigational New Drug (IND) exemption. This regulatory determination is a significant accelerator. Typically, advancing a drug into a Phase 2 trial requires submitting a full IND application, a process involving extensive preclinical data and a mandatory 30-day FDA review period.

The exemption was likely granted because PridCor’s regimen utilizes drugs that are already FDA-approved and lawfully marketed in the U.S.—valacyclovir, celecoxib, and Paxlovid. Under federal regulation 21 CFR Part 312, such an exemption can be granted if the investigation does not introduce a new route of administration, dosage, or patient population that would significantly increase the known risks of the drugs.

This does not, however, mean a lack of oversight. The SHIELD Study will still operate under the strict supervision of an Institutional Review Board (IRB) and must adhere to all informed consent requirements and Good Clinical Practice (GCP) standards. The exemption allows PridCor to bypass a time-consuming administrative step, enabling a more efficient transition into controlled clinical evaluation without compromising patient safety or ethical standards.

“These milestones strengthen both the scientific and regulatory underpinnings of our SHIELD Study,” said Dr. William Pridgen, Co-Founder and Chief Executive Officer of PridCor Therapeutics, in the company's press release. “Peer-reviewed publication confirms that our early clinical observations merit further investigation, and the IND exemption allows us to advance efficiently while maintaining rigorous ethical and regulatory standards.”

A Powerhouse Collaboration

Central to the SHIELD Study's promise is the high-caliber team leading the effort. The trial will be conducted in partnership with the Icahn School of Medicine at Mount Sinai, a leading institution in Long COVID research since the pandemic's early days.

The study will be led by Principal Investigator Dr. David Putrino, Director of Rehabilitation Innovation for the Mount Sinai Health System and the Nash Family Director of the Cohen Center for Recovery from Complex Chronic Illnesses. Dr. Putrino is a prominent figure in the field, having led groundbreaking research that identified distinct blood biomarkers in Long COVID patients, pointing to abnormal immune function and the reactivation of latent viruses like Epstein-Barr.

Joining him as Co-Investigator is Dr. Amy Proal, a microbiologist and President of the PolyBio Research Foundation. Dr. Proal is a leading proponent of the viral persistence theory, which posits that lingering SARS-CoV-2 reservoirs in tissues are a primary driver of Long COVID. Her foundation has been instrumental in funding and organizing collaborative research efforts to investigate this hypothesis. The involvement of both Dr. Putrino and Dr. Proal brings together deep expertise in both the clinical manifestations and the underlying molecular mechanisms of the disease, creating a powerful synergy for the trial.

A Crowded Field, A Distinct Approach

PridCor's therapy enters a competitive and rapidly evolving landscape. Numerous academic and commercial entities are racing to develop treatments for Long COVID, which affects millions worldwide and carries a staggering societal and economic cost. Other trials are also investigating Paxlovid, including the NIH-funded STOP-PASC trial at Stanford University, to see if the antiviral can help patients with established Long COVID.

Other therapeutic strategies being tested range from immunomodulators like baricitinib, which aims to quell the dysregulated immune response, to repurposed HIV antivirals and symptomatic treatments for fatigue and cognitive dysfunction. This diverse array of approaches reflects the complexity of Long COVID, which is likely not a single entity but a collection of syndromes with different underlying causes.

PridCor's strategy, rooted in the theory that persistent viral activity from both SARS-CoV-2 and reactivated latent viruses drives symptoms, is a targeted approach within this broader field. By combining multiple antiviral agents with complementary mechanisms, the company hopes to address a core driver of the illness in a subset of patients, potentially offering a more definitive treatment rather than just symptom management.