The virus hijacks that human protein to copy itself
No cruzamento entre a oncologia e a virologia, um composto espanhol já utilizado no tratamento do cancro emerge como candidato promissor contra a COVID-19 — não por atacar diretamente o vírus, mas por privar o agente patogénico de uma proteína humana essencial à sua sobrevivência. Os resultados publicados em Science, com uma redução de 99% da carga viral em modelos animais, relembram-nos que as respostas às crises mais urgentes da humanidade surgem, por vezes, de caminhos já percorridos.
- A plitidepsina reduziu a carga viral em 99% nos pulmões de ratos infetados, num resultado que os investigadores descrevem como potente e clinicamente relevante.
- O mecanismo de ação é invulgar: o fármaco bloqueia uma proteína humana — a eEF1A — que o SARS-CoV-2 necessita para se replicar, tornando o vírus dependente de um recurso que lhe pode ser retirado.
- A urgência de novos tratamentos coexiste com a cautela regulatória, mas o historial de segurança da plitidepsina em doentes oncológicos elimina uma das maiores incertezas no desenvolvimento de antivirais.
- A PharmaMar está em negociações com autoridades de saúde para avançar para ensaios de Fase III, o passo decisivo que poderá transformar dados laboratoriais em tratamento aprovado.
Um composto espanhol utilizado no tratamento de tumores revelou uma eficácia surpreendente contra o coronavírus em estudos animais. A plitidepsina reduziu em 99% a carga viral nos pulmões de ratos infetados em dois estudos independentes, com resultados publicados na revista Science. Os investigadores recomendam que o fármaco seja seriamente considerado para ensaios clínicos alargados em doentes com COVID-19.
O que torna a plitidepsina distinta de outros antivirais experimentais é o seu mecanismo de ação: em vez de atacar diretamente o vírus, bloqueia a proteína humana eEF1A, da qual o SARS-CoV-2 depende para se replicar e disseminar. Ao interromper este processo, o fármaco priva o agente patogénico de uma ferramenta essencial à sua sobrevivência — uma abordagem que mostrou ser simultaneamente eficaz e com um perfil de toxicidade gerível.
O facto de a plitidepsina já ter sido administrada a seres humanos no contexto oncológico representa uma vantagem significativa: o seu perfil de segurança é conhecido, eliminando uma das maiores incertezas no desenvolvimento de novos medicamentos. A PharmaMar, empresa produtora do composto, encontra-se já em negociações com reguladores de saúde para iniciar ensaios de Fase III — a etapa final antes de uma eventual aprovação —, o que indicia confiança nos dados pré-clínicos e vontade de avançar rapidamente.
A Spanish antiviral compound has shown striking promise in early laboratory work against the coronavirus. Researchers testing plitidepsina—a drug already in use for cancer treatment—found it reduced viral load by 99 percent in the lungs of infected rats across two separate animal studies. The results, published Tuesday in the journal Science, suggest the compound may warrant serious consideration for human trials.
Plitidepsina works by blocking a human protein called eEF1A, which the virus depends on to replicate and spread to other cells. By interrupting this mechanism, the drug essentially starves the pathogen of a tool it needs to survive. The researchers behind the work emphasize that the antiviral effect was both potent and accompanied by a manageable toxicity profile—a crucial combination when evaluating any potential treatment.
What distinguishes plitidepsina from many experimental antivirals is that its safety record in humans is already established. The drug has been used clinically to treat tumors, meaning developers do not face the usual uncertainty about whether a compound will prove tolerable in people. This prior knowledge reduces a significant hurdle in drug development and could accelerate the path to human testing.
The team conducting the research, which involved laboratories in France and the United States, argues that plitidepsina deserves expanded clinical trials. They note that while toxicity concerns are legitimate for any antiviral candidate, the existing human safety data for this particular compound addresses that worry. The researchers call for the drug to be "seriously considered" for larger-scale clinical evaluation in COVID-19 patients.
PharmaMar, the company that produces plitidepsina, is already in discussions with multiple health regulators about moving forward. The goal is to initiate Phase III trials—the final stage of testing before potential approval—which would involve hundreds or thousands of patients and provide the definitive evidence needed to determine whether the drug actually works in real-world conditions. The company's regulatory negotiations suggest confidence in the preclinical data and a readiness to move quickly if authorities give the green light.
Notable Quotes
Plitidepsina should be seriously considered for expanded clinical trials in COVID-19 treatment based on positive preclinical data and initial clinical results— Research team publishing in Science
The Hearth Conversation Another angle on the story
Why does it matter that this drug was already used for cancer? Couldn't any compound be tested for COVID?
Because safety in humans is the hardest part to prove. PharmaMar doesn't have to start from scratch proving the drug won't poison people—they already know the dose ranges that work. That saves months or years.
The 99 percent reduction sounds almost too good. Should we be skeptical?
Healthy skepticism is warranted, but animal studies often show stronger effects than human trials do. That's why Phase III exists. The real question is whether that 99 percent translates to actual patients with actual immune systems fighting back.
What does blocking this eEF1A protein actually do to the virus?
It cuts off the virus's ability to copy itself. The virus hijacks that human protein to manufacture new viral particles. Without it, the infection stalls.
How long until we know if this works in people?
Phase III could take months to a year or more, depending on how quickly patients enroll and how the disease progresses in the trial. There's no shortcut through that process, even with promising early data.
Is PharmaMar betting everything on this, or is it one of many shots they're taking?
It's one of several approaches the company is pursuing, but given the regulatory momentum and the existing safety data, this one has a clearer path forward than most experimental antivirals.