Getting To Know Paxlovid, Pfizer's COVID-19 Drug Claimed To Have Up To 90 Percent Efficacy

Paxlovid, Pfizer's COVID-19 drug is seen being manufactured in Ascoli, Italy, in this undated flyer photo obtained by Reuters on November 16, 2021. (ANTARA/Pfizer/Handout via REUTERS/pri)

JAKARTA - Associate Professor from the department of chemistry at Universiti Putra Malaysia Bimo Tejo, Ph.D. said that the drug Paxlovid is effective for all variants of the COVID-19 mutation.

According to him, this is because the target is a protease enzyme, a virus whose mutation rate is much lower than the mutation in the spike section of the SARS-CoV-2 virus.

In late December 2021, the United States Food and Drug Administration (FDA) approved an emergency use authorization (EUA) for Paxlovid in the treatment of COVID-19.

The availability of drugs as special oral therapy for SARS-CoV-2 is urgently needed to minimize the effects of COVID-19 on the body and prevent hospitalization, as well as illness and death.

In clinical trials, Paxlovid was 90 percent effective in preventing hospitalization and death of high-risk patients. In addition, paxlovid was also able to fight VOC Sars Cov-2, including Omicron. Paxlovid has also been reported to inhibit other coronaviruses, including SARS and MERS.

Paxlovid will be available as a blister containing two 150 mg Nirmatrelvir tablets and one 100 mg Ritonavir tablet. Nirmaltrevir is derived from candidate drug PF-00835231, which was created by the pharmaceutical company Pfizer to tackle the SARS outbreak in 2002.

However, the drug production process was stopped because the SARS outbreak was brought under control quickly.

The drug candidate PF-00835231 was only glimpsed after the emergence of COVID-19 caused by the SARS-CoV-2 virus, which is a beta coronavirus, a group with the virus that caused the SARS outbreak that emerged 20 years ago.

The Pfizer research team also modified the drug candidate PF-00835231 to increase its effectiveness against the SARS-CoV-2 virus. The result of this modification is named nirmaltrevir (PF-07321332).

Nirmaltrevir works by inhibiting the protease enzyme used by the SARS-CoV-2 virus to reproduce in the human body. The result is that the development of the virus is inhibited.

Because nirmaltrevir has the possibility to decompose in the human body (thus reducing its effectiveness), ritonavir is added to maintain the stability of nirmaltrevir so that it does not break down easily.

The results of the Paxlovid clinical trial (nirmaltrevir and ritonavir) by Pfizer involving 2,246 people showed an 89 percent effectiveness in reducing the risk of hospitalization and death if given 3 days after symptom onset, or 88 percent if given 5 days after symptom onset.

In addition, in the Paxlovid clinical trial the Asian population was included in the clinical trial subjects. Its composition is 72 percent Caucasian, 5 percent African, and 14 percent Asian. So the effectiveness of Paxlovid against people of Asian race has been tested.

Furthermore, as quoted by Antara, Bimo explained that Paxlovid is safe for consumption by COVID-19 patients aged 12 years and over and weighing 40 kg or more. However, Bimo reminded that Paxlovid is not effective for COVID-19 patients with severe symptoms and who have been treated in the hospital.

This drug must also be given as soon as it is indicated positive for COVID-19, preferably within 5 days after the appearance of symptoms, and cannot be used for more than 5 consecutive days. Bimo also emphasized that Paxlovid can only be given through a doctor's prescription.