Spanish biotech Tetraneuron presented an upstream gene‑therapy approach—TET‑101—using AAV to modulate the transcription factor E2F4, aiming to halt neuronal cell‑cycle reentry and restore memory in Alzheimer’s models. Company leadership described the mechanism as acting upstream of amyloid and tau pathologies, potentially addressing multiple neurodegenerative drivers reported by founders from José Frade’s laboratory. Tetraneuron’s CEO discussed the program at the European Cell & Gene Therapy Summit; the company contends the approach could translate into durable cognitive benefits if safety and delivery hurdles in humans can be managed. The program remains preclinical but represents an “upstream” strategy distinct from amyloid‑ and tau‑targeted modalities.