the longer people hesitate for perfect proof, the more opportunities slip away
Semanas depois de reguladores nos Estados Unidos, no Reino Unido e na União Europeia, a Anvisa autorizou na quarta-feira o uso emergencial do Paxlovid, antiviral da Pfizer contra a Covid-19, para adultos em situação de risco. O medicamento, que combina dois antivirais para bloquear a replicação do vírus, demonstrou reduzir em 89% o risco de hospitalização e morte em pacientes vulneráveis. A aprovação chega num momento em que o Brasil busca ferramentas para encerrar a emergência sanitária, e especialistas veem nos antivirais um complemento essencial às vacinas na proteção da vida humana.
- O Brasil demorou mais de seis semanas para aprovar um medicamento que outros países já haviam autorizado meses antes, levantando questões sobre o ritmo da resposta regulatória em meio à pandemia.
- Adultos de alto risco — aqueles que testaram positivo mas ainda não precisam de oxigênio suplementar — seguiram sem acesso a um tratamento capaz de evitar que sua condição se agravasse.
- A Anvisa aprovou o Paxlovid com restrições claras: apenas para adultos, por no máximo cinco dias, com prescrição médica, excluindo gestantes, pacientes com doença renal grave e casos já hospitalizados.
- Pesquisadores alertam que o medicamento mantém eficácia contra a variante ômicron e que aguardar certeza absoluta antes de agir significa perder janelas terapêuticas preciosas para pacientes em risco.
- O ministro da Saúde, Marcelo Queiroga, sinalizou que o acesso a tratamentos precoces eficazes é condição necessária para o Brasil declarar o fim da emergência de saúde pública.
A Anvisa aprovou na quarta-feira o uso emergencial do Paxlovid, antiviral da Pfizer contra a Covid-19, mais de seis semanas após receber o pedido em meados de fevereiro. O medicamento já havia sido autorizado por reguladores dos Estados Unidos, do Reino Unido e da União Europeia meses antes.
O Paxlovid é indicado para adultos que testaram positivo para Covid-19 mas ainda não necessitam de oxigênio suplementar — justamente o grupo com maior risco de evoluir para quadros graves, hospitalização ou morte. Ele combina dois antivirais: o nirmatrelvir, desenvolvido pela Pfizer, e o ritonavir, medicamento já consagrado no tratamento do HIV. Juntos, bloqueiam uma enzima essencial para que o vírus se replique no organismo. Estudos clínicos mostram redução de 89% no risco de hospitalização ou morte em adultos vulneráveis.
A aprovação vem acompanhada de restrições importantes. O uso é limitado a adultos, por no máximo cinco dias, mediante prescrição médica. Não é indicado para pacientes já hospitalizados, nem para prevenção pós-exposição. Gestantes devem evitar o tratamento, assim como pacientes com doença renal grave. Farmacêuticos terão papel central na orientação sobre o uso correto e possíveis interações medicamentosas.
Especialistas ouvidos pela reportagem destacaram que os antivirais representam um avanço significativo no arsenal terapêutico brasileiro, complementando as vacinas na redução de mortes e hospitalizações. O ministro Marcelo Queiroga reforçou, em evento em Brasília no mesmo dia, que o acesso a tratamentos precoces eficazes é um dos fatores determinantes para o Brasil encerrar a emergência sanitária.
Evidências iniciais indicam que o Paxlovid mantém eficácia contra a variante ômicron — uma vantagem em relação a anticorpos monoclonais, muitos dos quais perderam potência frente à variante. A pneumologista Kawano Dourado, pesquisadora do HCOR e colaboradora do grupo de diretrizes da OMS, explicou que antivirais como o Paxlovid dificilmente perdem efetividade com novas variantes, dado seu mecanismo de ação. Ela alertou que esperar por certeza absoluta antes de adotar tratamentos disponíveis significa desperdiçar oportunidades reais de salvar vidas.
Brazil's health regulator gave the green light on Wednesday to Paxlovid, Pfizer's antiviral treatment for COVID-19, clearing a medication that had already won approval from regulators in the United States, Britain, and the European Union months earlier. The Anvisa agency had received the application in mid-February but took more than six weeks to reach its decision during a meeting of its governing board.
The drug is designed for adults who have tested positive for COVID-19 but are not yet sick enough to require supplemental oxygen—people at high risk of deteriorating into severe illness, hospitalization, or death. It works by combining two antivirals: nirmatrelvir, a new compound developed by Pfizer and BioNTech, and ritonavir, an older drug long used in HIV and AIDS treatment. Together, they block an enzyme the virus needs to replicate inside the body. Clinical studies show the combination reduces the risk of hospitalization or death by 89 percent in vulnerable adults.
The approval comes with clear boundaries. Paxlovid is for adults only, requires a doctor's prescription, and cannot be used for more than five days. It is not authorized for patients already hospitalized with severe or critical COVID-19, nor for prevention before or after exposure. Because there is no safety data from pregnant women, the agency recommends avoiding pregnancy during treatment and for seven days after finishing the course. Patients with severe kidney disease are also excluded, as the proper dosage for that population has not been established. Pharmacists will be responsible for dispensing the medication and must counsel patients on how to take it correctly and watch for drug interactions.
Experts consulted by the news outlet emphasized that adding cutting-edge COVID treatments to Brazil's public health system matters significantly. These antivirals are highly effective at preventing hospitalizations and, alongside vaccines, represent a crucial tool for reducing illness and death from the disease. Health Minister Marcelo Queiroga underscored this point during an event in Brasília on the same day, stating that access to effective early-stage COVID medications is one of the determining factors for Brazil to declare an end to the public health emergency.
Initial evidence suggests Paxlovid remains potent against the omicron variant, a question that has shadowed other COVID treatments. Three studies released by Pfizer indicate the drug maintains its antiviral activity against coronavirus variants, including omicron. Kawano Dourado, a pulmonologist and researcher at HCOR's Institute of Research who contributes to the World Health Organization's COVID guideline development group, explained that antivirals like Paxlovid are not expected to lose effectiveness against new variants because of how they work—unlike monoclonal antibody treatments, many of which have faltered against omicron. She cautioned against waiting for absolute certainty before deploying treatments: the longer people hesitate for perfect proof, the more opportunities slip away for patients to benefit from what works now.
Notable Quotes
Access to effective COVID treatments like Paxlovid is one of the determining factors for Brazil to declare an end to the public health emergency— Health Minister Marcelo Queiroga
Antivirals like Paxlovid are not expected to lose effectiveness against new variants because of how they work, unlike monoclonal antibody treatments— Kawano Dourado, pulmonologist and WHO COVID guideline contributor
The Hearth Conversation Another angle on the story
Why did it take Brazil six weeks to approve something the FDA cleared back in December?
Regulatory processes vary. Brazil's Anvisa received the application in February and needed time to review the data, run it through their board. It's not unusual for different countries to move at different speeds, even when the underlying science is the same.
So this drug—it's not a vaccine replacement, right?
Correct. It's a treatment you take after you've already tested positive, in those early days when you're at risk of getting much sicker. Vaccines prevent infection or reduce severity. Paxlovid tries to stop the virus from replicating once you're already infected.
An 89 percent reduction in hospitalization sounds remarkable. Is that real?
That's what the clinical trials showed in vulnerable adults. But it matters who you are—the drug is only approved for people without severe disease yet, people who can still be treated at home. It's not for people already in the hospital fighting for breath.
The pregnancy restriction seems cautious.
It is. There's simply no data on safety in pregnant women, so the agency recommended avoiding pregnancy during and for a week after treatment. That's the responsible position when you don't have the evidence.
Does this actually change anything for ordinary Brazilians?
It depends on access. The approval is one thing; getting the drug into people's hands is another. But the Health Minister framed it as essential to declaring the emergency over. That suggests the government sees it as important infrastructure for moving past the crisis phase.
And it works on omicron?
Early studies say yes. The way these antivirals work—blocking an enzyme the virus needs—means they're less vulnerable to variant drift than some other treatments. But the expert quoted made a good point: you can't wait for perfect certainty. At some point you have to act on what you know.