AstraZeneca (AZN) appears to be stepping back from combination therapy approaches in transthyretin amyloid cardiomyopathy following a significant phase 3 clinical failure.
The setback involved Wainua, a drug developed in partnership with Ionis Pharmaceuticals (IONS), which failed to deliver the results needed to support a combination treatment strategy.
Despite the high-profile stumble, a number of analysts are pushing back against the idea that combination approaches in ATTR-CM are finished.
The debate now centres on whether Alnylam Pharmaceuticals (ALNY) can succeed where the AstraZeneca and Ionis partnership fell short in this patient population.
Alnylam’s RNA interference silencing drugs remain under consideration for patients who are already taking standard-of-care TTR stabilizers, according to analyst commentary following the trial news.
The question of combining silencing drugs with stabilizers is scientifically compelling, as the two mechanisms target the disease through different but potentially complementary pathways.
TTR stabilizers work by binding to the transthyretin protein to prevent it from misfolding, while silencing drugs aim to reduce production of the protein altogether at the genetic level.
Analysts who remain cautious about writing off the combination approach argue that the Wainua failure may reflect trial design or patient selection issues rather than a fundamental flaw in the underlying science.
AstraZeneca’s decision to move away from the combo strategy does represent a meaningful signal to the market, given the resources and expertise both it and Ionis brought to the programme.
However, Alnylam’s silencing platform has demonstrated strong standalone efficacy data in ATTR-CM, which gives some analysts confidence that its drugs could still hold up in combination settings.
The ATTR-CM market is a fiercely competitive space, with multiple companies racing to establish leadership across different mechanisms of action and patient segments.
Any ability to demonstrate added benefit in patients already stabilised on standard-of-care treatments could represent a significant commercial and clinical opportunity for whichever company cracks the combination code.
Alnylam has not publicly confirmed or detailed specific plans for pursuing combination trials in response to the AstraZeneca and Ionis outcome, leaving the market to watch closely for any strategic updates.
Investors in both Alnylam and the broader RNA therapeutics sector will be monitoring upcoming data readouts and conference presentations for any signals about the direction of combination research.
The coming months are likely to prove decisive in determining whether combination therapy in ATTR-CM remains a viable frontier or whether the field pivots firmly toward monotherapy approaches.