Hyperkalemia, elevated serum potassium, is a potentially life-threatening complication caused by a disruption of potassium homeostasis within the body. The kidneys play a vital role in managing potassium homeostasis, largely through control of potassium excretion. As a result, patients with renal insufficiency, such as those with chronic kidney disease or diabetic kidney disease, face an elevated risk of developing hyperkalemia. To further exacerbate the risk, patients with kidney disease receive renin-angiotensin-aldosterone system inhibitors (RAAS) in the first-line – a drug class known to cause hyperkalemia. Transient or mild increases in serum potassium, typically defined as 5 - 5.3 mEq/L, often remain asymptomatic and untreated. However, consistent elevation of serum potassium may signal potential risks for severe disturbances of potassium homeostasis (> 6 mEq/L) which can lead to cardiac dysrhythmias and even sudden death.
Management of hyperkalemia can often be as simple adjusting potassium-inducing medications (e.g., RAAS inhibitors) or diet modifications, but may also require diuretics, sodium bicarbonate, insulin-glucose bolus, dialysis, and/or a potassium binder. Potassium binders remain the only treatment indicated for hyperkalemia, all other approaches are off-label, but are nonetheless recommended by guidelines. According to surveyed and interviewed nephrologists, the severity and frequency of hyperkalemia dictates the treatment approach.1,2
Research by Decision Resources Group on G7 hyperkalemia drug-therapy market (United States, France, Germany, Italy, Spain, United Kingdom, Japan) forecasts an increase in sales from $323 million in 2016 to $2.4 billion in 2026.1 As of 2016, the market is dominated largely by older, inexpensive therapeutics options, with the explosion in sales stemming from the emergence of two potassium binders, Relypsa/Vifor Pharma’s Veltessa (patiromer) and AstraZeneca’s Lokelma (sodium zirconium cyclosilicate). Veltassa is already marketed in the United States, while Lokelma is awaiting approval of its regulatory application following two major hurdles with its manufacturing process which has significantly delayed market launch in the U.S. and Europe. Once approved, Lokelma and Veltassa will compete directly for a narrow subset of patients that face routinely elevated levels of serum potassium, resulting in erosion of sodium and calcium polystyrene sulfonate sales and patient share in the major markets. The boom in sales within the hyperkalemia market is driven by the hefty price tag on the two new binders – not on expanded uptake. Experts view efficacy and safety from the two therapies’ pivotal trials positively, however, caution that the need for such binders is limited to a small group of their patients. According to surveyed physicians, approximately 35% of their chronic kidney disease patients with elevated serum potassium are considered to have chronic hyperkalemia.2 Additionally, utilization of the new binders will be constrained by market access factors, a familiar challenge to all premium-priced therapies. Already, physicians report prior authorization challenges and requirements to demonstrate prior failed use with generically available sodium polystyrene sulfonate (Concordia’s Kayexalate). According to Vifor Pharma’s recent report, 53% of prescriptions require prior authorization for Veltassa.3
The new potassium binders provide new efficacy and safety benefits, but, like all new innovation, come at a price. Unless Vifor Pharma and AstraZeneca can shift physician attitudes away from halting RAAS inhibitors and towards continuous binder pharmacotherapy, market penetration of Veltassa and Lokelma will be limited. The Hyperkalemia Disease Landscape & Forecast report includes detailed epidemiology, sales, and patient share for both the chronic and acute hyperkalemia markets. Differences treatment practice, drug therapy use, and dosing necessitated the division of the market in order to elucidate key trends over time.
Click here to learn more about the forecast sales and patient share in the acute and chronic hyperkalemia G7 markets.
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1 DRG. Disease Landscape & Forecast | Hyperkalemia | G7 [Last updated: November 2017]
2 DRG. Current Treatment | Hyperkalemia | United States [Last updated: November 2017]
3 Vifor Pharma. H1 Investor Presentation, October 2017.