1. Dr. Venu Raman, professor of radiology, oncology and pharmacology at the Johns Hopkins University School of Medicine, explains that COVID-19 vaccines, so far, have relied on preventing the binding of a SARS-CoV-2 surface protein, spike protein, to host cells and enabling infection. However, if the spike protein changes with new variants, a vaccine’s effectiveness may be weakened.
2. The current method uses a small molecule inhibitor (about 1 nanometer), RK-33, to block the virus’s ability to take over a host cell’s “genetic manufacturing plant” and make copies of itself. And, Dr. Venu Ramen's study shows that RK-33’s antiviral capability is unaffected by spike protein mutations and remains consistent across four SARS-CoV-2 variants.
3. According to the news report, Dr. Raman has studied a ribonucleic acid (RNA) helicase, DDX3, and its anti-cancer activities. It is a protein that a protein that unwinds the double-stranded RNA controlling many tumor cells, enabling the RNA’s genetic code to be read (or translated). Consequently, this action leads to the creation of new cancer cells and malignant spread of the disease. Dr. Raman's study shows that RK-33 can slow down cancer progression by keeping RNA from unwinding for translation.
4. It is unknown that DDX3 protein also promotes the infectivity of many RNA viruses, including HIV and respiratory syncytial virus (RSV). Consequently, RK-33, the DDX3-inhibitor has a great potential for being as a cancer fighter, thus, it may also be a broad-spectrum antiviral agent. Dr. Raman's next step is to see whether RK-33 could work on SARS-CoV-2 as well.
5. Dr. Raman and his team used RK-33 to target DDX3 in laboratory cells infected with four variants of SARS-CoV-2 — the original virus and the alpha, beta and delta variants. And they found RK-33 treatment of infected cells showed significant reductions in the viral load. And, the RK-33’s antiviral activity is unaffected by the mutations that created each of them.
6. Dr. Raman explains that vaccines designed against the spike protein of one SARS-CoV-2 variant may not be as effective if a new variant has a mutated spike protein. On the other hand, the ability of RK-33 to inhibit DDX3’s unwinding of viral RNA for translation is independent of the spike protein, so it should be effective against most variants. Now, Dr. Raman and his team are working on to see if RK-33 can be as an antiviral against the omicron variant of SARS-CoV-2.
7. Currently, Raman holds a patent on the composition of RK-33.
8. It is exciting to hear this news. However, one may question how stable this protein in our body, how we dose the subjects with this protein, particularly the virus has affected different organs. Below is the link for the original news report:
