SHELTON, CONNECTICUT -- Thursday, August 4, 2022 -- NanoViricides, Inc. (NYSE American: NNVC) (the "Company"), a global leader in the development of highly effective antiviral therapies based on a novel nanomedicines platform, reports that it has begun drug development to combat the monkeypox virus.
Specifically, the Company has initiated a program to screen its library of broad-spectrum antiviral nanoviricides against certain poxviruses in order to develop broad-spectrum poxvirus therapeutics that act by mechanisms other than tecovirimat (TPOXX®).
"We are excited to act rapidly to develop much needed, safe and effective monkeypox therapeutics," said Anil R. Diwan, Ph.D., President of the Company, adding, "We are confident of developing a strong drug to treat the monkeypox virus infection, based on our recent successes in developing clinic-worthy drugs against human coronaviruses (including SARS-CoV-2 variants that have continued the evolution of COVID-19 global pandemic) as well as Shingles."
The Company is about to complete the synthesis of most of the compounds it intends to screen from its library of compounds that have shown broad-spectrum effectiveness against certain viruses. In addition, the Company has also developed a cell culture model for testing the effectiveness of these compounds against poxviruses similar to the monkeypox virus (MPXV) in its own BSL2 Virology Lab (MPXV itself requires a BSL3 Lab, but related viruses can be tested in a BSL2 Lab).
The impending human clinical trials of the Company's lead SARS-CoV-2 drug candidate, NV-CoV-2, are anticipated to enable a rapid timeline to success in the Company's Monkeypox Initiative. The Company intends to use the active component of NV-CoV-2, namely NV-387, as a delivery vehicle, to attack the monkeypox virus with additional "weapons" encapsulated within NV-387. The Company has already developed a number of such potential additional "weapons" that could be valuable for monkeypox virus treatment during its work on DNA-Virus families including the herpesviruses and adenoviruses.
Additionally, the Company expects that it may be possible to encapsulate tecovirimat (the active component of TPOXX®, SIGA) within the NV-387 nanomicelles, to improve its safety and PK/PD over the current delivery mode which is complexation with a cyclodextrin component that is known to lead to adverse reactions in renally impaired (i.e. kidney damage) patients.
NV-387 was shown to be safe in multiple animal studies and its safety is due to be evaluated in human clinical trials for which the Company has mostly completed the documents needed for an application. The Company has been working on initiating these clinical trials in multiple countries. The Company has also demonstrated the ability of NV-387 to encapsulate and improve the pharmacokinetics and pharmacodynamics of a very difficult drug, namely remdesivir, that is formulated in a cyclodextrin-based formulation at present (Veklury® Gilead).
The global monkeypox outbreak was declared a "Public Health Emergency of International Concern" ("PHEIC") by the World Health Organization (WHO) on Saturday, July 23, 2022 as cases have continued to surge exponentially since the first known case in the current outbreak was identified in May, 2022 (https://www.theguardian.com/world/2022/jul/23/monkeypox-who-declares-public-health-emergency-of-international-concern?CMP=oth_b-aplnews_d-1).
Since then, the monkeypox outbreak has continued to expand exponentially, with the global number of cases approximately doubling every two weeks, at over 23,000 reported confirmed cases in 88 countries as of August 1, 2022, and about 4,900 cases in the USA alone as of July 29, 2022 (https://www.monkeypoxmeter.com/).
The White House is expected to declare the current Monkeypox Outbreak a public health emergency very soon, as reported in Politico (https://www.politico.com/news/2022/07/27/biden-admin-monkeypox-health-emergency-00048333).
There is no approved drug for the treatment of Monkeypox virus infection, although TPOXX (tecovirimat, SIGA) is being provided from the US Strategic National Stockpile (SNS) to severely ill patients under an Expanded Access ("Compassionate Use) Investigational New Drug Protocol (EA-IND). TPOXX is approved by the US FDA under the "Animal Rule" for treatment of smallpox (a potential bio-weapon), with studies demonstrating efficacy against monkeypox virus infection in cynomolgus macaques as part of the animal model studies.
It is known that TPOXX resistant viruses develop readily by mutations in its target gene. Therefore, development of new medical countermeasures is warranted.
On July 29, the US FDA provided an update in which they stated that there is no FDA-approved or authorized medicine for the treatment of monkeypox disease; however, TPOXX (tecovirimat), an antiviral medication, is being made available through the CDC under an FDA authority called "Expanded Access" or "Compassionate Use". The FDA also stated that in 2019, the FDA approved the Jynneos Vaccine (Modified Vaccinia Ankara-BN strain) for the prevention of smallpox and monkeypox in adults 18 years of age and older determined to be at high risk of infection. Jynneos is the only vaccine approved for the prevention of monkeypox in the United States. The FDA further stated that the Centers for Disease Control and Prevention (CDC) has a FDA-cleared non-variola orthopoxvirus diagnostic test that can detect monkeypox by a swab from a monkeypox lesion (rash or growth). (https://www.fda.gov/news-events/press-announcements/fda-provides-update-agency-response-monkeypox-outbreak).
The Company's top priority remains initiating human clinical trials of its SARS-CoV-2 drug candidate NV-CoV-2 to combat COVID-19. The Company believes it is very close to filing a clinical trial application for COVID-19, although the timelines are outside of the Company's control.
The Company intends to develop both systemic treatments (injectable and oral treatments) to control monkeypox virus infection, as well as possibly a skin cream for topical treatment of the monkeypox rash, if successful. The Company has developed systemic injectable and oral formulations of its drug candidate NV-CoV-2 for treating SARS-CoV-2 variants that are continuing to extend the COVID-19 pandemic. Previously the Company has developed a broad-spectrum antiviral skin cream to topically treat the Shingles rash. Monkeypox is unrelated to the chickenpox virus that causes Shingles although both are DNA viruses. The Company has no expectation that the shingles drug candidate may be effective against monkeypox rash.
TPOXX (tecovirimat, SIGA Therapeutics), is a drug approved for smallpox under a special US FDA authority called the Animal Rule. It is stockpiled in the Strategic National Stockpile (SNS) in the U.S.A. in preparation for a potential bioterrorism attack. This drug is being released for use as a treatment of monkeypox virus infection. However, the risk-benefit profile of the drug for approval as a smallpox therapeutics may have allowed for acceptability of significant side effects.
Tecovirimat inhibits exit of the virus from cells by an orderly egress process. However, a single virus infecting a human cell produces 10,000 to 15,000 new progeny virus particles, and most of these virus particles are released upon cell lysis, rather than through the orderly egress pathway, limiting the utility of its mechanism of action.
Additionally, the risk of the virus mutating away from the drug is a well-known concern for tecovirimat. Thus, there are known limitations on the utility of tecovirimat.
Clearly there is an immediate and urgent need for the development of novel drugs against monkeypox that act by non-traditional mechanisms of action.
Dr. Tedros Adhanom Ghebreyesus, the WHO's director general, took the initiative in declaring a PHEIC, while the WHO Committee responsible for the decision was deadlocked. Globally, there were then about 16,000 monkeypox cases in about 75 countries. Monkeypox is endemic in West Africa, where the currently spreading virus variant appears to have originated. Additionally, a more lethal variant of monkeypox is endemic in Central Africa. Thousands of cases of monkeypox occur annually in these African regions. A vaccination campaign is not expected to be able to eliminate monkeypox because it has many animal species reservoirs.
If the current variant of monkeypox has improved upon its ability for human to human transmission, then it is imperative that highly active therapeutics need to be developed against this virus. The rapid rise in cases appears to indicate that such mutations may have occurred. The virus currently is thought to require direct skin-to-skin or close contact, limiting its spread to specific promiscuous cohorts. However, its spread via respiratory short-range droplets (not aerosol) is thought to be occurring as well. Thus the virus has or can develop the potential to spread widely into the general population. Fortunately, unlike SARS-CoV-2, the current monkeypox outbreak does not appear to have a high fatality rate. COVID-19 began with a case fatality rate of well over 10% and is now at a much lower fatality rate, about 3 in 1000, although the statistics are now based on incomplete datasets. Monkeypox in contrast, had 5 fatalities in 1600 cases so far in the current outbreak. Nevertheless the DRC variant of monkeypox is known to have as high as 30% case fatality rate in Central Africa, This is why the WHO's Director General took the unprecedented step of declaring a PHEIC. Declaration of PHEIC by the WHO is expected to increase focus of nations and regional authorities to devote resources to combatting this outbreak.
The Company believes it can successfully develop a drug candidate against poxviruses in a relatively short period of time, if one or more of its existing pipeline candidates or other nanoviricide candidates in its drug candidate library are found to be effective. To this end, the Company has developed an antiviral assay for testing these drug candidates against infection by certain poxviruses in cell cultures in its own BSL2 Virology facility. If cell culture studies are successful, the Company intends to progress its active drug candidates into animal model studies for the purpose of identifying a clinical candidate, and then rapidly progress to additional IND-enabling studies.
It is unlikely that a vaccination campaign can eliminate monkeypox because it has many animal species reservoirs. Monkeypox infects a wide range of small animals including rodents, prairie dogs, as well as large animals including monkeys and humans. In contrast, smallpox does not have any animal reservoirs, and only humans are its host, which enabled its elimination. Smallpox was eliminated around 1980 after successful global vaccination campaigns. Smallpox now exists only in a very few well guarded labs in the world for scientific purposes.
NanoViricides is one of a few biopharma companies that has its own cGMP-compliant manufacturing facility. The Company intends to produce its drugs for clinical trials in this facility. The Company has the capability to produce sufficient drugs for about 1,000-5,000 patients in a single batch of production, depending upon the drug and the dosage. This production capacity is anticipated to be sufficient for the Phase I and Phase II human clinical trials for our anti-coronavirus drug candidate NV-CoV-2, as well as for the production of necessary amounts of doses for a potential monkeypox virus therapeutic, and the anticipated clinical trials of NV-HHV-101 skin cream for the treatment of shingles.
The Company is in the process of completing a clinical trial application for its COVID-19 drug candidate, NV-CoV-2, and the filing is expected to occur soon. Additionally, the Company has completed IND-enabling studies for another drug candidate, NV-HHV-101 for the treatment of shingles rash caused by reactivation of the chickenpox virus (aka varicella-zoster virus, VZV). The Company plans on further developing the shingles drug candidate into human clinical trials after clinical trials of our COVID-19 drug candidate. The Company has additional drugs in its pipeline at various pre-clinical stages that it plans to develop towards regulatory approvals after the COVID-19 and Shingles drug clinical trials.