Cholesterol levels are set to be a key topic at the three-day American College of Cardiology Medical Conference that closes out the month in Washington, DC.

On the agenda: PCSK9 inhibitors, which are among the latest experimental treatments in the fight against high levels of cholesterol. A pre-game review by Jefferies analysts indicates that being new is not necessarily enough to position PCSK9s as the next critical innovation in heart health.

Jefferies analyst Jeffrey Holford noted in his Tuesday summary that PCKS9s have to contend with several challenges before it will be clear where the experimental drugs may fit in with a cardiologist’s treatment regimen. These include cardiovascular outcomes studies and clinical trial results of drugs in the rival CETP (cholesterylester transfer protein) inhibitor class. Holford writes that CV data won’t begin rolling in until 2017 or 2018, and results for CETP inhibitor trials are due in 2015 or later.

Despite the lag time, Holford writes that a firm survey of 50 cardiologists indicates physicians are ready to incorporate the unproven PCSK9s into their standards of care for high-risk patients. Jefferies’ survey indicated that doctors expected to prescribe PCSK9s to 10% to 23% of their high-risk patients before CV outcomes data is tallied, and that this number would rise to 29% to 37% of patients if the drugs were shown to have a cardiovascular benefit.

Holford says this inclination means the PCSK9 inhibitor market—which includes contenders from Amgen, Sanofi/Regeneron and Pfizer—could have $5 billion in US sales one year after launch, without CV outcomes information, and around $12 billion in US sales by 2019 if CV outcomes trials support their use. The analyst expects prescriptions would cost around $7,000 per year, and wrote that the surveyed cardiologists said they “would expect a cost greater than $5,000.”

Despite what appears to be a built-in audience the PCSK9 market may be limited. Bernstein’s Tim Anderson noted in a January assessment that his team thinks the treatments amount to a niche product—the drug is considered appropriate for patients with rare lipid conditions as well as  patients who cannot tolerate or do not respond to statins.

PCSK9s are also injections. Anderson wrote that an oral PCSK9 inhibitor would be “the holy grail” of this type of therapy. Jefferies’ Holford somewhat agrees, but notes in his March analysis that 30% of cardiovascular disease patients are diabetics, which means needles may not be an issue for this patient group. He also notes that RA patients “have around a 2- to 3-fold increase in the risk of cardiovascular disease compared to the general population.” They, too, are accustomed to needles, which could also make this group more amenable to an injectable cholesterol fighter.

Analyses by Holford and his Jefferies colleague Eun Yang indicate that as narrow as the applicable patient populations may be, the drugs may have a back door, which is to offer a lower-cost of LDL control for rare disease patients who are taking drugs such as Aegerion’s Juxtapid. Yang projects that Amgen’s evolocumab could cost around $10,000 a year, versus Juxtapid’s $295,000.

At the same time, CETPs may make it harder for PCSK9s to enter the heart market, partly because they are orals, and because studies have shown Merck’s anacetrapib and Eli Lilly’s evacetrapib lower LDL levels about around 40% and increase HDLs by more than 100%.  Holford notes that negatives in this category matter, and cited how a slight increase in blood pressure ended Pfizer’s CETP inhibitor torcetrapib, because  it “ultimately outweighed positive lipid changes when it was assessed for CV benefit.” Eighty-two patients died in the torcetrapid clinical trial that ended Pfizer’s development of the drug.

Yang wrote on Monday that a consulting expert cardiologist pins the success of CETP inhibitors on positive CV outcomes.