COVID-19: Drugwatch – 6 April 2020

To date, there are no approved treatments for COVID-19. However, the pharmaceutical industry is abuzz with activity as medical researchers strive to develop a cure, and possibly a vaccine, for the illness caused by the novel coronavirus. In this article, we have attempted to explore some of the more popular treatments / preventive measures that are presently being investigated or recommended as part of emergency treatment regimens.

Anti-HIV Drugs

Lopinavir is a protease inhibitor that is used for treating HIV-1 infection. This molecule had previously demonstrated in vitro activity against the SARS-CoV strain. In fact, a study of lopinavir, and the protease inhibitor, ritonavir, demonstrated clinical efficacy in treating human severe acute respiratory syndrome (SARS). However, in a study involving a  total of 199 patients with laboratory-confirmed SARS-CoV-2 infection, no clinical benefit was observed with lopinavir–ritonavir treatment.

Chloroquine and Hydroxychloroquine

“If it does work, it would be a shame if we didn’t do it early.”

Donald Trump

Primarily driven by President Trump’s what do you have to lose? attitude, the US and other nations have ramped up the production of chloroquine and hydroxychloroquine. Interestingly, experts have not voiced any positive opinion regarding the actual therapeutic benefits of the drug in treating COVID-19. The US FDA has not approved the use of the aforementioned drugs for treating the novel coronavirus related illness. However, the regulator has made provisions facilitating the distribution of the drugs from the US national stockpile. There are several concerns related to the side effects of these drugs, which need to be taken into consideration.

Convalescent plasma from COVID-19 survivors

“What we believe happens is that, for those individuals that have recovered from COVID-19, the level of antibodies that they have in their plasma is substantial enough to help someone else who is actually still in the throes of the disease recover quicker”

Elizabeth Waltman, Chief Operating Officer, South Texas Blood and Tissue Center

On 4 April 2020, the FDA approved the use of convalescent plasma, from COVID-19 survivors, to treat patients suffering from the disease. Almost immediately, the South Texas Blood and Tissue Center revealed its intentions to support the cause, putting out a request for plasma donations from recovered patients. It is worth noting that this therapy was approved as an investigational new drug. This means that there still isn’t enough evidence of the efficacy of this procedure. However, clinical trials are underway across the nation, in order to study the safety and efficacy of convalescent plasma to treat COVID-19. Interestingly, this procedure was used during the Spanish Influenza epidemic of 1918. It had also demonstrated some clinical benefits during the Ebola outbreak (2014).

Remdesivir: A shelfed miracle?

“Gilead started research into remdesivir more than a decade ago. We are now in a position to consider its potential to treat COVID-19 and rapidly progress its development and these clinical trials will help generate important data on the safety and efficacy of the medication in the coming weeks”

Hilary Hutton-Squire, Vice President and General Manager, Gilead Sciences (UK & Ireland)

On 6 April 2020, Gilead Sciences issued a notification stating that it has significantly ramped up remdesivir manufacturing. Moreover, the company gifted 1.5 million doses of the experimental drug (from existing supplies) for COVID-19 treatment, across the world. Presently, two Phase III randomized studies, evaluating the safety and efficacy remdesivir in patients with moderate to severe COVID-19, are underway.

“Providing our existing supplies at no charge is the right thing to do, to facilitate access to patients as quickly as possible and in recognition of the public emergency posed by this pandemic”

Daniel O’Day, Cheif Executive Officer, Gilead Sciences

It is worth highlighting that the molecule was rapidly pushed through clinical trials during the West African Ebola epidemic (2013–2016). Having demonstrated promising results and a promising safety profile, it was also used during the Kivu Ebola epidemic of 2018. However, it was later demonstrated to be significantly less effective than monoclonal antibody treatments, namely mAb114 and REGN-EB3, which were developed against the aforementioned conditions, respectively. As a result, the molecule was shelved until the novel coronavirus outbreak in late 2019.

After preliminary studies showed the therapeutic potential of the drug in treating the novel coronavirus infection, Gilead rapidly initiated trials across multiple jurisdictions in order to gather the necessary evidence of its effectiveness against the disease. Not to mention, this sent the company’s share prices skyrocketing in an otherwise declining economy. Although a lot of effort is being put into remdesivir, there are chances that more specific therapies (biologics) may once again disrupt the currently envisioned market potential of the molecule.

Other Drug Candidates

In addition to repurposing older drugs as potential treatment options for COVID-19, contemporary drugmakers have resorted to exploring certain novel antibodies and developing vaccines in order to combat the SARS-CoV-2 pandemic. So far, these are the only three strategies at the pharma industry’s disposal, against the pandemic. The image below provides a summary of other interventions that are being evaluated for treating the novel coronavirus infection.