PCSK9 inhibitors recommended for limited patient groups.
By Louisa Joseph, Analyst
22 June 2015
A US Food and Drug Administration (FDA) committee has endorsed Praluent (alirocumab; Sanofi/Regeneron) and Repatha (evolocumab; Amgen/Astellas) solely for high-risk hypercholesterolemia patients, with further outcomes data needed for broader approval.
The FDA’s Endocrinologic and Metabolic Drugs Advisory Committee (EMDAC) has supported approval of the PCSK9 inhibitors Praluent and Repatha, but only for a limited number of high-risk hypercholesterolemia patients. It is unlikely that these PCSK9 inhibitors will be approved for the broader dyslipidemia patient population until large-scale cardiovascular outcomes trials (CVOTs) can demonstrate the drugs’ beneficial clinical effects.
On 9–10 June, the EMDAC voted that the low-density lipoprotein cholesterol (LDL-C)-lowering benefits of Praluent and Repatha outweighed the risks associated with their use in certain high-risk patient populations. Both drugs were recommended for the treatment of patients with heterozygous familial hypercholesterolemia, a genetic disease that is associated with unusually high levels of LDL-C and a higher risk of heart attacks at a young age. Repatha was also unanimously recommended for patients with homozygous familial hypercholesterolemia, a rarer form of the disease that is associated with early-onset atherosclerosis and severely elevated levels of LDL-C. However, given the very low numbers of familial hypercholesterolemia patients in the US, the commercial opportunities for the PCSK9 inhibitors in these treatment settings are limited.
The committee declined to endorse the drugs for use in broader dyslipidemia treatment settings due to the lack of CVOT data. Despite the drugs’ observed abilities to lower LDL-C by an additional 60% when compared to standard therapy alone, the panelists were cynical with regard to how this effect would translate into cardiovascular benefit and whether the benefits would be sufficient to support widespread use. Both drugs have large-scale CVOT trials underway, with the results of Amgen’s FOURIER trial and Sanofi/Regeneron’s ODYSSEY outcomes trial expected by the end of 2017. These results will be necessary for the FDA to properly access clinical potential in the broader pure hypercholesterolemia and mixed hyperlipidemia markets.
Moreover, the results of the large-scale CVOTs will also be vital for driving uptake of these costly drugs. With prices for the injections predicted at around $10,000 per patient per year, health insurers and pharmacy benefit managers are unlikely to recommend their use unless they demonstrate clear long-term clinical benefits and satisfactory safety profiles. If the ongoing CVOTs are successful, it is likely that the PCSK9 inhibitors will gain approval for broader use in the dyslipidemia market, giving the drug class the potential for multi-billion dollar sales. For now, however, it seems that commercial revenues for these drugs will be limited, with approval expected solely for the high-risk familial hypercholesterolemia patient populations.