UK Alzheimer's drug lecanemab approved but NICE says too costly; Tyche satellite launch and butterfly declines featured on Naked Scientists

The Naked Scientists cover major science stories from medicine to space. The MHRA approves the Alzheimer's drug lecanemab, but NICE says the clinical benefits do not justify the cost, raising NHS access questions. The UK MoD launches the Tyche Earth imaging satellite, while Butterfly Conservation details the dramatic decline in native butterflies. The episode also explores a novel silicification approach that could extend red blood cell shelf life and mask blood-group markers, potentially enabling universal donors.

Alzheimer’s drug lecanemab: regulation, cost, and timing

The episode opens with the MHRA's approval of lecanemab, an antibody aimed at reducing amyloid in the brain and slowing the progression of Alzheimer’s disease. While regulators in the NHS Medicines and Healthcare products Regulatory Agency have given the go‑ahead based on trial data, the National Institute for Clinical Excellence (Nice) has concluded that the benefits are not large enough to justify the roughly £20,000 per year per patient cost. The discussion explains that, although the drug can slow disease progression by about 25 percent and could extend the period of independence, it does not halt the disease. The experts emphasize that starting treatment earlier in the disease process yields better outcomes, but diagnostic windows in the general population are still a challenge. There is also debate about long‑term health‑economic considerations, including the balance of NHS costs against family costs and informal care, with Nice leaving the door open to revisiting the decision as real‑world data accumulate.

Silicification of red blood cells: potential universal donors

The program then covers a breakthrough in transfusion science. Researchers report a silicification approach that replaces calcium carbonate in red blood cells with silica to create a sturdier shell. This could extend shelf life beyond the current six weeks and mask blood‑group markers, potentially enabling universal transfusions. The host quizzes an expert about how the coating masks blood group antigens and whether the technique preserves cell function. Imaging shows silica presence inside cells, but researchers have not demonstrated long‑term circulation in vivo. The potential to store blood longer and tolerate harsher conditions, including cryopreservation, could alleviate shortages of universal donors like group O negative.

Tyche: the UK’s first Earth imaging satellite

In the space segment, the UK MoD announces Tyche, a small, washing-machine‑sized cube satellite designed for intelligence, surveillance and reconnaissance. Tyche can image the Earth with about one‑meter resolution, complementing aircraft and other space assets. The discussion covers orbit choices, including a polar sun‑synchronous low Earth orbit that keeps the satellite oriented toward the Sun, and onboard systems like an auxiliary compute peripheral and inter‑satellite link. The guests explain the propulsion, attitude control, and power management, including how the satellite uses reaction wheels and a dedicated propulsion system to maintain altitude and avoid debris.

Butterflies: population trends and practical action

Back on the ground, the Naked Scientists speak with Frank Gardner, BBC correspondent, about Butterfly Conservation’s findings that four of five native species have declined since the 1970s. Weather patterns, habitat loss, and pesticides are identified as major contributors, with Brimstone and Holly Blue doing relatively better this year. Gardner notes the caution required in interpreting causes and highlights the ecological consequences for birds and broader ecosystems due to fewer caterpillars available for feeding hatchlings.

Question of the Week: cobwebs and human touch

Finally, the program revisits a Question of the Week about why cobwebs feel odd when touched. Sara Goodacre from the Spider Lab explains that spider silks are a diverse and ancient set of proteins with varying stickiness and hydrophobic properties. The sensation is partly due to the interaction of silk with skin hairs and its unique molecular composition, which can feel different from other materials. The segment ends with next week’s question about how Earth would differ if the Moon-forming impact had not happened.

Closing notes

The Naked Scientists conclude by inviting listener participation via their forums and remind audiences that the show is produced in association with the Institute of Continuing Education at Cambridge and supported by industry partners.