Vaccine Info

Vyrologix (Leronlimab PRO 140) Antibody

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Last reviewed
September 22, 2021
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Robert Carlson, MD

Vyrologix Leronlimab (Pro 140) Description

CytoDyn's Vyrologix™ Leronlimab (PRO 140) is a CCR5 antagonist with the potential for multiple therapeutic indications. It belongs to a new class of HIV/AIDS therapeutics that protects healthy cells from viral infection. Vyrologix is a humanized monoclonal antibody targeted against the CCR5 receptor found on T lymphocytes of the human immune system. The CCR5 receptor plays a central role in modulating immune cell trafficking to sites of inflammation.

Vyrologix - Leronlimab, among various potential applications, is a viral-entry inhibitor in HIV/AIDS. It binds to CCR5, thus protecting healthy T cells from viral infection by blocking the predominant HIV (R5) subtype from entering those cells. Leronlimab does not work on other strains of HIV (for example, X4); however, R5 is the most dominant strain of HIV. 

Only two documented cases of HIV cure have been reported, the Berlin and London patients, who both were cured via allogeneic stem cell transplants from CCR5-deficient donors. However, in pre-clinical studies, Leronlimab has demonstrated the ability to mimic CCR5 deficiency by binding to CCR5 receptors, thereby preventing HIV from interacting with its primary co-receptor. 

Nader Pourhassan, Ph.D., CytoDyn's President and CEO, commented on September 8, 2021, "Today marks the first day of the much anticipated clinical trial in Brazil that we have been waiting for, and we are so grateful to our team who conducted the CD12 trial in the U.S. that produced a wealth of information for us to be able to appropriately design and power these two studies."

And on September 22, 2021, Pourhassan commented in a press statement: "We are excited about this (Brazil) news and what it means for leronlimab's potential ability to successfully treat critically ill COVID-19 patients in the future all over the world. We believe the IV treatment in this trial will have an enormous advantage over treatment via subcutaneous injections, which was the route of administration in our last COVID-19 trial (CD12) in the U.S. Furthermore, in our CD12 study, the survival benefit in the critically ill population was 78% after the first-week post the first dose of leronlimab and 82% after the second week.'

The U.S. FDA has designated Leronlimab (Pro 140) for Fast Track Approval to treat Human Immunodeficiency Virus and metastatic cancer. Leronlimab is a viral-entry inhibitor in HIV/AIDS. It binds to CCR5, thus protecting healthy T cells from viral infection by blocking the predominant HIV (R5) subtype from entering those cells. Leronlimab does not work on other strains of HIV (for example, X4); however, R5 is the most dominant strain of HIV.

Molecular Formula: C6534 H10036 N1720 O2040 S42.

Vancouver, Washington-based CytoDyn (OTCQB: CYDY) is a late-stage biotechnology company developing innovative treatments for multiple therapeutic indications using leronlimab, a novel humanized monoclonal antibody targeting the CCR5 receptor. CCR5 plays a critical role in the ability of HIV to enter and infect healthy T-cells. In addition, it appears to be implicated in tumor metastasis and immune-mediated illnesses, such as NASH.

Vyrologix Leronlimab (Pro 140) Indication

The Vyrologix leronlimab antibody appears to be a powerful antiviral agent leading to potentially fewer side effects and less frequent dosing requirements compared with daily drug therapies currently in use. Vyrologix Leronlimab (Pro 140) is in early clinical trials to treat COVID-19 disease. Leronlimab is intended to serve as a therapy for patients who experience respiratory illness due to contracting the Coronavirus Disease 2019 (COVID-19). These patients' treatment was not under the Company's proposed randomized, Phase 2 clinical trial protocol recently submitted to the FDA.

The "cytokine storm" is believed to play an integral role in developing acute respiratory distress syndrome (ARDS) in those affected by COVID-19. Chemokines and chemokine receptors play a critical role in the recruitment, activation, and coordination of leukocytes in lung inflammation's pathophysiology. The acute respiratory distress syndrome (ARDS) of COVID-19 results from the accumulation of neutrophils within the pulmonary circulation and alveolar spaces.

COVID-19 is caused by a coronavirus called SARS-CoV-2. Coronaviruses are a large family of viruses common in people and many different animals, including camels, cattle, cats, and bats.  Rarely, animal coronaviruses can infect people and then spread between people.

However, this occurred with MERS-CoV and SARS-CoV, and now with the virus that causes COVID-19. The SARS-CoV-2 virus is a betacoronavirus, like MERS-CoV and SARS-CoV.

Research may prove that leronlimab is a safe and effective option for treating people with R5-tropic virus (a strain of HIV), including those for whom other entry and fusion inhibitors, such as maraviroc (brand name: Selzentry), are not working. In the setting of HIV/AIDS, leronlimab is a viral-entry inhibitor; it masks CCR5, thus protecting healthy T cells from viral infection by blocking the predominant HIV (R5) subtype from entering those cells. Leronlimab has been the subject of nine clinical trials, each of which demonstrated that leronlimab could significantly reduce or control HIV viral load in humans.

Vyrologix Leronlimab (Pro 140) News

September 22, 2021 - CytoDyn Inc. announced that Brazil's regulatory authority, Agência Nacional de Vigilância Sanitária, has approved the start of a different Phase 3 CD16 clinical trial of leronlimab. The new clinical trial will focus on hospitalized COVID-19 patients in critical condition who require mechanical and invasive ventilation or Extracorporeal Membrane Oxygenation.

September 13, 2021 - CytoDyn Inc. (OTCQB: CYDY) announced Nader Pourhassan, Ph.D., President and CEO, and Scott Kelly, M.D., Chairman, and Chief Medical Officer, will provide a comprehensive business update at the upcoming Emerging Growth Conference. Previous investor presentations are available at this link.

September 9, 2021 - CytoDyn Inc. announced the treatment of the first patient in its pivotal Phase 3 COVID-19 trial in Brazil for patients with severe symptoms. An interim analysis will be conducted 28 days following the enrollment of 245 patients, 40% of the total number of patients enrolled in the trial.

August 26, 2021 - CytoDyn Inc. (OTCQB: CYDY) announced today Seenu Srinivasan, Ph.D., as Executive Director-CMC Regulatory Affairs.

August 3, 2021 - CytoDyn Inc. announced that Brazil's regulatory authority Agência Nacional de Vigilância Sanitária)has approved the previously submitted clinical trial protocol to commence patient enrollment in its CD17 trial for severe COVID-19 patients. The Academic Research Organization Albert Einstein Israelite Hospital in Brazil will conduct the trial.

July 19, 2021 - CytoDyn Inc. announced strong preliminary results from its Phase 1b/2 trials and compassionate use with a total of 30 metastatic triple-negative breast cancer (mTNBC) patients. Patients in Phase 1b/2 were treated with leronlimab in combination with carboplatin.

May 19, 2021 - According to Pharmaceutical Technology, CytoDyn is set to submit the results from the Phase III CD12 clinical trial of Vyrologix (leronlimab-PRO 140), seeking potential regulatory approval for the drug to treat severe to critically ill patients with Covid-19.

May 3, 2021 - CytoDyn, a late-stage biotechnology company developing leronlimab (Vyrologix™ or PRO 140), a CCR5 antagonist with the potential for multiple therapeutic indications, announced a comprehensive update three continuing extension studies with leronlimab as a treatment for HIV.

December 24, 2020 - CytoDyn Inc. announced the U.S. FDA guided the Company through adding an open-label extension to its Phase 3 trial ("CD12") and specific criteria for the continuation of for patients meeting the inclusion/exclusion criteria of CD12. Upon clearance, each CD12 participating clinical trial site will have the option of enrolling additional qualified patients, with all patients receiving leronlimab. In addition, treatment of qualified patients will continue until the trial's data is unblinded.

December 15, 2020 - CytoDyn Inc. announced it had reached full enrollment in its Phase 3 registrational trial for patients with severe-to-critical COVID-19. The 390-patient data will be analyzed in approximately 28 days, with expected results announced shortly thereafter.

November 23, 2020 - CytoDyn Inc., a biotechnology company developing Vyrologix™ (leronlimab-PRO 140), a CCR5 antagonist with the potential for multiple therapeutic indications, announced today it had reached an enrollment of 293 patients in its Phase 3 trial for COVID-19 patients with severe-to-critical symptoms, thereby meeting the requested criteria for a second interim efficacy analysis by the Data Safety Monitoring Committee.

November 17, 2020 - Washington-based CytoDyn Inc. announced it had filed a protocol with the U.S. FDA for a Phase 2 clinical trial for leronlimab to treat COVID-19 patients suffering from long-hauler symptoms.

October 26, 2020 - CytoDyn Inc. announced the Medicines & Healthcare product Regulatory Agency of the U.K. government had cleared CytoDyn to file its Biologics License Application (BLA) leronlimab as a combination therapy for multi-drug resistance HIV patients in the U.K.

October 20, 2020 - CytoDyn Inc. announced recommendations from the Data Safety Monitoring Committee following its review of the interim analysis of the Company's Phase 2b/3 registrational trial in patients with severe-to-critical COVID-19. The interim analysis was performed on data from the first 195 (50%) of 390 planned patients.

September 22, 2020 - CytoDyn's Phase 2 Study of Leronlimab for Mild-to-Moderate COVID-19 Selected for Oral Presentation at the Special isirv-AVG Virtual Conference on 'Therapeutics for COVID-19.'

July 21, 2020 - CytoDyn Inc. announced the results of the patient safety data from the Company's over-enrolled COVID-19 disease Phase 2 trial for treating mild-to-moderate indications. Just 5 patients out of 56 (about 9%) reported serious adverse events; none were related to leronlimab.

May 19, 2020 - CytoDyn Inc. announced it would coordinate with the NIH of Mexico and provide leronlimab for a trial for the severe - critical COVID-19 disease population in Mexico with the potential to collaborate on further collaboration CytoDyn COVID-19 trials. "The NIH of Mexico is committed to helping alleviate human suffering and mortality of Mexican citizens. The Metropolitan Area of the Valley of Mexico has a population of approximately 21.5 million people, and the contagious nature of COVID-19 is relentless," said Nader Pourhassan, Ph.D., President, and Chief Executive Officer of CytoDyn.

May 5, 2020 - CytoDyn Inc. announced a pre-print version of the manuscript had been made publicly available on posting with Research Square and MedRxiv describing the immunological mechanism by which leronlimab restores immune function and impacts disease in COVID-19 patients. As described in the pre-print, in a cohort of ten critically ill patients, after treatment with leronlimab, these critically ill patients experienced reversed hyperimmune activation and inflammation. In addition, they reversed immunosuppression, thereby facilitating a more effective immune response correlated with decreases in SARS-CoV-2 levels in the blood.

May 4, 2020 - CytoDyn Requests Compassionate Use from FDA for COVID-19 Patients Not Eligible for Participation in Two Ongoing Clinical Trials in the U.S. – CytoDyn Targets Enrollment Completion for its 75 Patient, Phase 2 Trial by the end of May.

April 7, 2020 - Novant Health is initiating patient enrollment in CytoDyn's Phase 2 randomized clinical trial for COVID-19 patients with mild-to-moderate infections.  Novant Health is the first site in the southeastern United States to initiate this Phase 2 trial.  And a  Phase 2b/3 trial will be for severe and critically ill COVID-19 patients.

March 19, 2020 - CytoDyn Inc. announced today that two coronavirus patients were treated with the Company's investigational new drug, leronlimab. The treatment was administered at a leading medical center in the New York City area under an emergency Investigational New Drug (IND) recently granted by the U.S. Food and Drug Administration (FDA).

Vyrologix Leronlimab (Pro 140) Clinical Trials

Cytodyn's Vyrologix is being studied in 5 clinical trials. On August 2, 2021, Brazil authorized a phase 3 study. This pivotal Phase 3 trial for severe COVID-19 patients is conducted by Academic Research Organization ("ARO") Albert Einstein Israelite Hospital. This trial intends to provide Brazil's regulatory authority ANVISA (Agência Nacional de Vigilância Sanitária) with the requisite data to consider advancing the availability of leronlimab to Brazilians infected with COVID-19. The trial will be conducted in up to 35 clinical sites with 612 patients who are hospitalized and in need of oxygenation support.

On July 21, 2020, the Phase 2 study announced 34% (19 of 56 patients) were treated with leronlimab compared to 50% (14 of 28 patients) treated with placebo reported at least one adverse event. A total of 19 serious adverse events (SAEs) were reported during the study. Eleven SAEs were reported in 6 patients (6/28; 21.4%) receiving placebo compared to eight (8) SAEs in 5 patients (5/56; 8.9%) receiving leronlimab. None of the SAEs in the leronlimab arm were deemed related to study drug administration by the investigators. Of the 84 patients treated, one patient died 33 days after enrollment due to an event unrelated to leronlimab.

To find out more about the clinical trials, please visit Cytodyn's clinical trial enrollment site.