anti-viral drug – BioQuakes

In the past few months, scientists in the United States have developed a potential new antiviral to SARS-CoV-2. The drug, called NMT5, is effective against several variants of SARS-CoV-2, the virus that sent the planet into lockdown only a few years ago.

As stated in the journal Nature Chemical Biology, NMT5 coats SARS-CoV-2 particles as they travel through the body. Thus, when the virus attempts to attach to the ACE2 receptor proteins of the cell, NMT5 attaches first. The drug changes the shape of the cell’s receptor upon attachment, which makes it harder for SARS-CoV-2 to infect the cell, and on a larger scale, the organism’s body.

In order to ensure that the drug isn’t toxic, researchers tested NMT5 on healthy cells. According to the National Institute Of Health, it was “found that NMT5 was non-toxic and only changed receptors that were being targeted by the virus. These effects lasted for only about 12 hours, meaning the receptors functioned normally before and after treatment”. In fact, in an experiment that used hamsters as models for the human immune system, NMT5 reduced SARS-CoV-2’s ability to bond to ACE2 receptors by 95%!

A significant reason NMT5 is so effective is that it not only limits one particle of SARS-CoV-2, but the effectiveness of the virus as a whole, when present. When a SARS-CoV-2 particle with NMT5 attaches to an ACE2 receptor, it adds a nitro group to the receptor, which limits the ability of the particle to attach to the receptor for 12 hours by changing the receptor’s shape. Thus, no COVID-19 particle can attach to the ACE2 receptor – even ones that haven’t been surrounded by NMT5. Stuart Lipton, a professor at The Scripps Research Institute, states that “what’s so neat about [NMT5] is that we’re actually turning [SARS-CoV-2} against itself”, as particles surrounded by NMT5 serve to limit the ability of other SARS-CoV-2 particles. The drug has excited scientists studying SARS-CoV-2 around the world, as they have “realized [NMT5] could turn the virus into a delivery vehicle for its own demise” (PTI, The Tribune India).

Cell reception and signaling are incredibly important to both viruses and the human immune system. A virus works by infiltrating a cell through cell receptors that line the outside of the desired cell’s phospholipid bilayer. Viruses attach to these receptors and infect the cell as a result. SARS-CoV-2’s process is depicted below, as it attaches to the ACE2 receptors described earlier. The immune system works by recognizing the virus at hand and signaling B-Lymphocytes and T-Lymphocytes to destroy the virus and infected cells. B-Plasma cells surround the virus, as shown below, which neutralize it and allow it to be engulfed and destroyed by macrophages. Cytotoxic T-cells kill cells already infected by the virus. Both B and T Lymphocytes are activated as a result of T-Helper cells, as T-Helper recognize the virus when a piece of it is displayed at the end of a macrophage, and signal the Lymphcytes by releasing cytokines (another example of cell reception and signaling). This process is all shown in the image below, with the specific virus depicted being SARS-CoV-2.

However, NMT5 prevents the initial infection from happening when SARS-CoV-2 enters the human body by bonding with SARs-CoV-2 particles before they attach to cells, which allows for the immune system to quickly destroy the virus. By blocking SARS-CoV-2’s access to receptors, the drug stops the particle before it can infect a cell and do any damage. Since cell receptors are specifically shaped, and any change in form results in a loss of normal function, the ensuing change in shape of a receptor limits any SARS-CoV-2 particle from attaching to said receptor, further limiting the virus’s damage by blocking cell reception from occurring. Thus, the immune system kills the virus without major symptoms.

All in all, the development of NMT5 is exciting for scientists all around the globe. If it is as effective as studies show, it could play a major role in limiting the effects of SARS-CoV-2. Hopefully, all goes well, and you should be hearing a lot more about the drug sometime soon.

If you have any updates or questions on NMT5, I invite you to share them in the comments below. Thank you for reading my blog post, and stay curious!

Right now, it seems like the only defense against the evasiveness of COVID is the vaccine. However, there has been a new emergence that might help alleviate some worries. This is the PAXLOVID anti-viral drug. This new drug is given to people with high-risk cases of COVID a few days after they are infected. Though, before this pill is approved, it has to run through many trials, and it has to be confirmed by the FDA (Food and Drug Administration). The numbers that are coming out of the trials of the drug are nothing short of astonishing….

Pfizer made the announcement that within 3 days of infection, the PAXLOVID drug reduces the risk of hospitalization or death by 89%. The trials for the drug were over a substantial amount of time. The numbers that have been received as of now are that out of 607 people tested, only 6 were hospitalized and NONE died. These are very promising numbers for the drug, and it is a big step towards approval. To further boost PAXLOVID’s credibility, placebo, a “control” drug was tested alongside PAXLOVID. This control drug is a fake pill to make people believe it is doing good for them. This is called the placebo effect. In the end, the fantastic numbers produced by PAXLOVID against placebo proved that PAXLOVID is the way to go and that it is a successful drug that actually works. Now you may be wondering how does this “anti-viral drug” work to defend against COVID?

The answer is not so simple. The primary goal for PAXLOVID, and any other anti-viral drug is to prevent the virus from replicating. As we learned in our biology class, the way a virus replicates itself is by entering the dendritic cell or macrophage, then it can actually copy RNA virus and take command of the cell, basically hijacking it. However, the anti-viral drug is made up of two clear components that instead of interfering with RNA copying enzyme, it blocks something else. The drug has the ability to inhibit Protease enzymes. Protease enzymes are mainly responsible for activating long strains of protein by cutting them down.

Altogether, PAXLOVID is a versatile, and very useful drug that we will likely be seeing and hearing more about in the near future. If you contracted COVID, would you be willing to take PAXLOVID?

BioQuakes

AP Biology class blog for discussing current research in Biology

Tag: anti-viral drug

NMT5: A New Enemy To SARS-CoV-2?

PAXLOVID: A Breath of Fresh Air?

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