Is This A Miracle Drug For 'Sticky Cholesterol'? Analysts Applaud Safety, Efficacy Of Silence Therapeutics' Heart Disease Candidate

Earlier today, Silence Therapeutics plc SLN announced topline results from the multiple-dose component of the APOLLO phase 1 study of zerlasiran (formerly SLN360) in 36 adults with baseline lipoprotein(a) (Lp(a), levels at or over 150 nmol/L and stable atherosclerotic cardiovascular disease (ASCVD). 

The data demonstrated a significant reduction from baseline in Lp(a) of up to 99% at 90 days following injection of repeated doses. Lp(a) levels remained approximately 90% lower than baseline at 201 days (end of treatment period) at the two highest doses. 

A dose-dependent reduction in low-density lipoprotein cholesterol (LDL cholesterol) and apolipoprotein B (ApoB) was also observed. 

Zerlasiran was well tolerated; no clinically important safety concerns were identified.

Zerlasiran is currently being evaluated in the fully enrolled ALPACAR-360 phase 2 study in patients with Lp(a) levels at or over 125 nmol/L at high risk of ASCVD events. 

Silence expects to report topline 36-week data in Q1 of 2024 and topline 48-week data in Q2 of 2024.

HC Wainwright writes that the reductions in Lp(a) demonstrated in the multiple-dose component appear to be clinically relevant.

The analyst sees zerlasiran potentially generating peak annual revenues of $2 billion-plus annually in Lp(a). It reiterates the $80 price target and Buy rating.

Although the press release lacked specific details, William Blair regards the significant and long-lasting reductions in Lp(a) levels in the study as a positive development. This outcome further enhances zerlasiran's competitive standing compared to other RNA-targeted peers.

Furthermore, the absence of elevated CRP or neutrophil levels at these highly effective doses represents a clear victory when compared to previous 600mg single ascending dose (SAD) data.

Price Action: SLN shares closed up 29.30% at $8.66 on Wednesday.