The process is laborious and time-consuming. Not every patient who could benefit has been able to access it.
En una sala de reuniones en Santander, hematólogos españoles se congregaron para contemplar el horizonte de los tratamientos contra el cáncer de sangre, conscientes de que las terapias CAR-T actuales, aunque transformadoras, aún no llegan a todos quienes las necesitan. La próxima generación de estas terapias —que reprogramaría las células inmunitarias directamente dentro del cuerpo del paciente— representa no solo un avance técnico, sino una promesa de mayor equidad en el acceso a la medicina. Como ocurre con todo progreso genuino, el camino entre la evidencia temprana y la práctica clínica generalizada se mide en años de paciencia y rigor científico.
- Las terapias CAR-T actuales salvan vidas, pero su fabricación individualizada puede tardar semanas, dejando a muchos pacientes sin acceso a tiempo.
- El enfoque in vivo —que usa virus modificados o nanopartículas lipídicas para reprogramar células inmunitarias directamente en el cuerpo— podría comprimir meses de proceso en apenas días.
- Un estudio con el virus modificado KLN-1010 presentado en Orlando mostró resultados clínicamente significativos y un perfil de seguridad comparable al de las terapias convencionales, generando expectativa en la comunidad científica.
- Las células CAR-T alogénicas, obtenidas de donantes sanos, abren otra vía para eliminar la fabricación personalizada, aunque plantean el reto del rechazo inmunológico.
- Los expertos advierten que pasar de datos prometedores en poblaciones pequeñas a uso hospitalario rutinario tomará probablemente cinco años o más, siguiendo el mismo camino que recorrió la primera generación de estas terapias.
El mes pasado, hematólogos españoles se reunieron en Santander para analizar los avances presentados en el congreso anual de la Asociación Americana de Hematología en Orlando. El foco no estaba en los logros actuales, sino en lo que viene después.
Las terapias CAR-T llevan años en uso y sus resultados son sólidos: se extraen células inmunitarias del paciente, se reprograman en laboratorio para atacar células cancerosas y se reinfunden como un medicamento vivo. Sin embargo, Felipe Prósper, investigador de la Clínica Universidad de Navarra, subrayó sus limitaciones: el proceso es lento, laborioso y no todos los pacientes que podrían beneficiarse logran acceder a él a tiempo.
La siguiente generación busca eliminar esos cuellos de botella. El enfoque in vivo prescinde por completo de la extracción celular: virus modificados o nanopartículas lipídicas transportan instrucciones genéticas directamente al interior del cuerpo, reprogramando las células inmunitarias del paciente sin que estas salgan jamás de él. Entre los quinientos estudios presentados en Orlando, uno con el virus KLN-1010 destacó por sus resultados clínicamente relevantes y su perfil de seguridad comparable al de las terapias convencionales. Aun así, Prósper fue claro: los datos provienen de poblaciones pequeñas, y el salto a la práctica hospitalaria no es automático. La primera generación de CAR-T tardó cinco años en recorrer ese camino.
Otra estrategia en exploración son las células CAR-T alogénicas, obtenidas de donantes sanos. Un solo lote modificado podría, en teoría, tratarse a múltiples pacientes, eliminando la espera de la fabricación personalizada, aunque introduce el desafío de la compatibilidad y el rechazo inmune.
Lo que emerge de estas conversaciones es un campo en transición: las terapias actuales han demostrado su valor, pero siguen siendo lentas, costosas e inaccesibles para muchos. La próxima generación promete ser más rápida y más equitativa, pero esa promesa aún se mide en años de validación clínica, no en meses de entusiasmo.
In a conference room in Santander last month, Spanish hematologists gathered to discuss the future of blood cancer treatment. The occasion was a review of research presented at the American Hematology Association's annual meeting in Orlando—hundreds of studies on how to improve therapies that have already transformed outcomes for patients with cancers of the blood and bone marrow. But the real focus was on what comes next.
CAR-T therapies have been in use for years now, and by most measures they work. Doctors extract immune cells from a patient's own body, reprogram them in the laboratory to recognize and attack cancer cells, then infuse them back into the patient as a living drug. The results have been substantial. Yet as Felipe Prósper, a researcher at the University Clinic of Navarra in Pamplona, explained to the assembled experts, these treatments carry significant limitations. The process is laborious and time-consuming. Manufacturing a dose for a single patient requires weeks of careful work. The complexity means not every patient who could benefit has been able to access the therapy.
The next generation of CAR-T approaches aims to sidestep these bottlenecks. One strategy, called in vivo CAR-T, eliminates the extraction-and-reinfusion step entirely. Instead of removing cells from the patient, scientists now design modified viruses or tiny lipid nanoparticles—microscopic fat-based containers—that carry genetic instructions directly into the body. Once injected, these vehicles reprogram the patient's immune cells in place, turning them into cancer fighters without ever leaving the body. It is a fundamentally different approach, one that could compress months of manufacturing into days.
Proof of concept is emerging. Among the five hundred studies presented in Orlando, one stood out enough to warrant special attention from the conference organizers. Researchers using a modified virus called KLN-1010 achieved clinically meaningful results in patients with blood cancers. Equally important, the safety profile resembled that of conventional CAR-T therapy—no unexpected toxicities, no alarming side effects. But Prósper was careful to note a crucial caveat: these results come from small patient populations. The leap from promising early data to standard hospital practice is not automatic. It took five years, he reminded the room, to move the first CAR-T therapies from laboratory evidence to clinical approval and routine use. The in vivo approaches will likely follow a similar timeline.
A second avenue under exploration involves allogeneic CAR-T cells—immune cells harvested from healthy donors rather than from patients themselves. The advantage is obvious: a single batch of donor cells, once modified and validated, could theoretically be administered to many patients, eliminating the wait for personalized manufacturing. This approach trades the complexity of individual cell extraction for the logistical challenge of finding compatible donors and managing immune rejection.
What emerges from these discussions is a field in transition. Current CAR-T therapies have proven their worth, but they remain slow, expensive, and inaccessible to many who need them. The next generation promises to be faster, potentially cheaper, and more widely available. Yet promise is not yet practice. The researchers gathering in Santander were not celebrating breakthroughs so much as mapping the road ahead—identifying which strategies show enough early signal to justify larger, longer studies. For patients waiting for these therapies to mature, the timeline remains measured in years, not months.
Citas Notables
Current CAR-T therapies have achieved great results, but they also have significant limitations— Felipe Prósper, University Clinic of Navarra
It took between 2012 and 2017 to move the scientific evidence to approval and clinical practice with the first CAR-T therapies— Felipe Prósper
La Conversación del Hearth Otra perspectiva de la historia
Why does it take so long to move from a promising study to something a patient can actually receive?
Because you're not just proving a therapy works—you're proving it's safe enough to give to thousands of people. A small study might show ten patients responding well. But what happens in patient number five hundred? You need to know.
So the in vivo approach—injecting instructions directly into the body—that's genuinely different from what they do now?
Fundamentally. Right now they're taking cells out, working on them for weeks in a clean room, then putting them back. In vivo skips all that. The virus or nanoparticle does the work inside you. It's elegant if it works.
And the allogeneic approach—using donor cells instead of your own?
That's the manufacturing dream. One batch of cells, many patients. But you're introducing foreign cells into someone's body. The immune system notices. You have to solve that problem first.
Prósper mentioned it took five years for the first CAR-T to go from lab to clinic. Are we looking at that timeline again?
Probably longer, actually. The first ones had urgency—desperate patients, no alternatives. Now the bar is higher. You need bigger studies, longer follow-up. Five to ten years is realistic.
What's the human cost of waiting?
Patients who could benefit today but can't access current CAR-T because it's too complex or too slow. They're the reason researchers are pushing so hard on these new approaches.