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<p class="" data-start="0" data-end="433"><span style="font-family: georgia, palatino, serif; font-size: 12pt;">A recent study from Stanford University warns that CAR-T cell therapy&mdash;hailed for its success against aggressive cancers&mdash;may also trigger a form of &ldquo;brain fog,&rdquo; characterised by forgetfulness and difficulty concentrating. CAR-T therapy involves extracting a patient&rsquo;s T cells, genetically reprogramming them to target cancer cells, and reinfusing them into the bloodstream to bolster the body&rsquo;s antitumor response.</span></p>
<p class="" data-start="435" data-end="1051"><span style="font-family: georgia, palatino, serif; font-size: 12pt;">Researchers induced tumours in mice in various locations&mdash;the brain, blood, skin, and bone&mdash;to explore how CAR-T treatment affects cognition across different cancer types. Using standard behavioural assays, including novel-object recognition tests and simple maze navigation, they found that mice developed mild cognitive impairments after CAR-T infusion regardless of whether their tumours were in, had spread to, or lay entirely outside the brain. The only exception was mice with bone-only tumours, which elicit minimal collateral inflammation beyond the cells&rsquo; antitumor activity&mdash;and did not exhibit such deficits.</span></p>
<p class="" data-start="1053" data-end="1324"><span style="font-family: georgia, palatino, serif; font-size: 12pt;">Further investigation identified microglia, the brain&rsquo;s resident immune cells, as the prime mediators of these side effects. When CAR-T cells incite inflammatory signals, microglia become overactivated and interfere with the neural circuits underlying memory and focus.</span></p>
<p class="" data-start="1326" data-end="1893"><span style="font-family: georgia, palatino, serif; font-size: 12pt;">Importantly, the study also tested pharmacological interventions that dampen microglial overactivation, successfully reversing the cognitive issues in treated mice. These findings suggest that pairing CAR-T therapies with targeted drugs could safeguard patients&rsquo; mental clarity without compromising the treatment&rsquo;s life-saving potential. As CAR-T continues to revolutionise cancer care, understanding and mitigating its long-term neurological effects will be crucial to ensuring survivors not only live longer, but also maintain the quality of their cognitive health.</span></p>
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While revolutionary against cancer, CAR-T therapy could trigger cognitive side effects like forgetfulness and difficulty concentrating

CAR-T Cell Therapy May Cause Brain Fog, Says Stanford Study

While revolutionary against cancer, CAR-T therapy could trigger cognitive side effects like forgetfulness and difficulty concentrating

May 13, 2025 | 22:44 IST