Why High-Risk Patients Still Need Antivirals: Q&A with Gurinder S. Sidhu, M.D.

In a conversation with Pharmaceutical Executive, Dr. Gurinder S. Sidhu, senior medical director and U.S. Antiviral Medical Lead, Pfizer discussed the continued risk Covid-19 poses to high-risk patients, even as some clinicians have grown more inclined to deprioritize antiviral treatment amid declining hospitalization rates compared to the early pandemic.

Sidhu noted that between October 2024 and September 2025, the CDC estimated 380,000 to 540,000 Covid-19-associated hospitalizations in the U.S., with roughly 75% of American adults falling into high-risk categories due to age (50 and over) or underlying conditions such as diabetes, heart disease, obesity, or asthma. He pointed to guidance from the Infectious Disease Society of America (IDSA), which has recognized that patients with more than one underlying health condition face heightened risk for severe disease, compounded by evidence that Covid-19 can worsen long-term health outcomes or contribute to new medical conditions.

Sidhu emphasized that Pfizer views each patient's care as requiring a customized approach made in collaboration with their doctor, underscoring prescription options like Paxlovid (nirmatrelvir 150mg tablets; ritonavir 100mg tablets) as an important consideration for eligible patients, given the narrow five-day window from symptom onset within which treatment must begin.

In the conversation, Sidhu also addressed persistent barriers to antiviral treatment access, ranging from cost to awareness to the rebound conversation that created hesitancy, and affirmed Pfizer's commitment to working across the healthcare system, from patients to healthcare practitioners to payors and insurers, to ensure broad, equitable access to treatment for adults at high risk of Covid-19 progression.

A transcript of Sidhu's conversation with Pharmaceutical Executive can be found below.

Pharmaceutical Executive: High-risk patients are still getting seriously ill and being hospitalized from Covid-19. What's your message to clinicians who may have deprioritized antiviral treatment as part of their standard of care?
Dr. Gurinder S. Sidhu: It’s understandable that some clinicians may consider deprioritizing treatment given the number of hospitalizations today has reduced compared to the early pandemic days, however high-risk patients continue to be impacted by Covid-19. Between October 2024 and September 2025, the CDC estimates between 380,000 to 540,000 Covid-19–associated hospitalizations in the U.S.

Approximately 75% of American adults are at high risk for progression to severe Covid-19, which includes those 50 and over, as well as those with certain underlying medical conditions such as diabetes, heart disease, obesity, or asthma. Those considered high risk may face potentially stark outcomes like severe illness, hospitalization, or death.

The Infectious Disease Society of America (IDSA) has also recognized that patients with more than one underlying health condition can be at an increased risk for progression to severe disease, and with approximately half of U.S. adults having multiple chronic conditions, their Covid-19 risk can heighten. There is also evidence of severe cases of Covid-19 having an impact on long-term health, such as developing new medical conditions or making preexisting conditions worse.

At Pfizer, we recognize that each patient is unique and requires a customized approach to their care plan, made in collaboration with their doctor. We firmly believe in the benefits of incorporating prescription medicine into the consultation discussion, where appropriate. For those eligible, prescription medicines like Paxlovid (nirmatrelvir 150mg tablets; ritonavir 100mg tablets) remain an important consideration for patient care. And, because they need to be started within a 5-day window of symptom onset, waiting to see how and whether symptoms progress can mean the difference between being able to prescribe/obtain a prescription for an antiviral medication versus missing the opportunity for treatment. Currently, the role of Paxlovid in long-term post-Covid-19 outcomes has not been established.

PE: Access has been a persistent challenge, from cost to awareness to the rebound conversation that created hesitancy. What is Pfizer doing to make sure the patients who need treatment receive it?
Dr. Sidhu: We agree that there is need for adults who are at high risk of progression to severe Covid-19 to have access to safe and effective treatment options, such as Paxlovid, to help prevent hospitalization, deaths and severe illness or outcomes.

Pfizer continues to work with all parts of the healthcare system, from patients, to healthcare practitioners (HCPs), to payors and insurers, to ensure broad, equitable access to our medicines.

We are proud to offer cost-saving options through Paxcess patient support program, where eligible, commercially insured patients may access Paxlovid for as little as $0*, and eligible Medicare, Medicaid and uninsured patients may access Paxlovid for free. 

Regarding viral rebound, the CDC has examined a variety of data among both patients who did and did not take prescription treatment for Covid-19 and have not identified any consistent association between treatment and viral rebound. The CDC suggests that, per NIH Guidelines, viral rebound should not deter providers from prescribing antiviral treatments when indicated.

PE: The data behind Paxlovid spans clinical trials to millions of real-world patients. What does that kind of evidence base tell us about how the drug performs in the real world?
Dr. Sidhu: Multiple real-world analyses, including those conducted during the Omicron era, have illustrated the safety and effectiveness of Paxlovid in preventing severe outcomes from Covid-19 infection, among eligible patients. This growing body of evidence highlights the important role that Paxlovid plays in supporting eligible patients, providers, and health care systems around the world.

Covid-19 has been a very fast-moving virus, and, during my time at Pfizer, I’ve seen Sars-CoV-2 variants change and evolve at a rapid pace. While the population’s level of immunity has fluctuated, so too has their day-to-day concern with the virus and its potential impact. That’s why Pfizer is committed to working with the wider scientific community to continue research into Covid-19, both in clinical and real-world settings. We will continue to broadly share and reinforce these findings as able.

PE: What gives you the most optimism about where antiviral treatment is headed and what concerns are raised?
Dr. Sidhu: With Covid-19, our ongoing concern is the unpredictable nature of the virus, as disease severity can vary drastically with each infection based on factors such as circulating variants, waning immunity, and individual immune function. A patient’s individual experiences with Covid-19 will not all be the same, regardless of how they may have responded to the virus in the past, so timely care remains absolutely essential.

But I remain optimistic about the future of prescription medicines to treat Covid-19 in eligible patients, and the role they will continue to play in the broader care landscape. With an estimated three-quarters of Americans falling into the CDC’s definition of those at “high risk” of getting very sick from the virus, and based on the wealth of clinical and real-world evidence we have to support the appropriate use of Paxlovid, we believe it will remain an important tool for physicians to employ in helping treat Covid-19 and mitigate severe outcomes for appropriate patients. This is particularly important at a time when fewer preventative strategies are being deployed or considered by many Americans.

The more we learn about the virus and its potential to impact long-term health for example, by exacerbating underlying health conditions or even leading to new onset conditions, it will be important for prescription medicine to remain part of care discussions patients are having with their doctors.