Thalia Therapeutics (AIM:THAT) announced on Wednesday that it has completed an in vitro study for its cardiovascular gene-silencing programme, THAT-002, hitting the target objectives needed to advance into in vivo studies.
The London-listed, AIM-quoted clinical-stage biotech, which develops RNA-based therapeutics and delivery technologies for oncology and cardiovascular disease, has renamed the programme Lipisiran.
Lipisiran is designed as a potentially long-duration, dual-acting siRNA therapeutic targeting both PCSK9 and lipoprotein(a), two independent drivers of cardiovascular disease risk, with the aim of a single agent reducing the global risk of heart attack and stroke.
The programme reached this stage quickly: Thalia completed the initial chemistry synthesis underpinning THAT-002 in September, clearing the way for the in vitro work now reported, with preclinical research conducted alongside WuXi AppTec in Hong Kong.
The in vitro study, run in human liver cells, tested whether Thalia's bispecific siRNA constructs could lower levels of both PCSK9 and Lp(a) in target cells, and all four constructs tested showed positive results indicating engagement with both therapeutic targets.
The constructs lowered both PCSK9 and Lp(a) as effectively as when the individual siRNA sequences were administered separately, a result Thalia says validates its thesis for a dual-acting therapeutic.
Thalia has now begun a series of in vivo studies to establish efficacy and durability, the next stage on the path toward IND-enabling development and FDA filing for human clinical studies.
"Showing that our bispecific constructs can lower the targets PCSK9 and Lp(a) as effectively as the individual siRNA sequences is a significant step forward in validating our thesis," said Dr David Solomon, chief executive, pointing to Merck KGaA's proposed roughly $1.3 billion acquisition of former AIM-listed Silence Therapeutics, which also has a mono Lp(a) gene-silencing medicine, as evidence of investor interest in next-generation siRNA medicines.
Read more about Thalia Therapeutics
- 29/09/26Thalia Therapeutics wins Chinese patent for miRisten
- 25/09/26Thalia completes chemistry synthesis for cardiovascular RNA drug
- 24/06/26Thalia Therapeutics acquires AML RNA therapy company in deal backed by £2.75m raise
The cardiovascular programme sits alongside Thalia's lead clinical asset, miRisten, an RNA therapy in Phase 1 trials for acute myeloid leukaemia acquired through the Sanmirna Therapeutics deal completed in July, with topline Phase 1 data for that programme expected in the first half of 2027.
Solomon said he would provide updates on Lipisiran "as and when appropriate" while determining the next investment and development steps.