Is this the biggest threat to GW Pharmaceuticals marijuana drug? – The fool

After being assured that the Food and Drug Administration (FDA) and the Drug Enforcement Agency (DEA) accept GW Pharmaceuticals (NASDAQ: GWPH) plans to launch her marijuana-derived epilepsy drug, Epidiolex, in six weeks. There is a huge unmet need for new treatment options for patients with epilepsy who do not respond to antiepileptic drugs. Optimism is therefore great for Epidiolex. The commercial success of the drug may, however, depend on regulatory approval of a drug Zogenix (NASDAQ: ZGNX).

A victory for marijuana in epilepsy

For years, patients have used cannabis strains rich in cannabidiol, a chemical cannabinoid found in marijuana and hemp, to control epilepsy, but no scientific study proving the effectiveness of CBD in epilepsy before the arrival of GW Pharmaceuticals.

SOURCE OF IMAGE: GETTY IMAGES.

To obtain an FDA certification for Epidiolex, GW Pharmaceuticals has conducted four separate studies that have proven that Epidiolex can safely reduce seizures in patients with Dravet syndrome and Lennox-Gastaut syndrome, two rare types of Epilepsy of childhood.

In his trials, Epidiolex reduced monthly seizures by 40% to 50%, which is remarkable as these patients typically experience dozens of gout attacks each month, despite the use of existing antiepileptic drugs. For example, the median Lennox-Gastaut patient in the Epidiolex trials had 71 gout seizures per month initially and was taking three antiepileptic drugs.

The trial data and the significant need for new therapeutic alternatives for these patients resulted in the FDA's approval of Epidiolex in June and the DEA rewarding Epidiolex with the Schedule V classification, its category the least restrictive prescription.

An imminent threat

The imminent launch of Epidiolex is a milestone for GW Pharmaceuticals, as Epidiolex will be its first commercial product available in the United States. There are an estimated 30,000 patients with Dravet syndrome and Lennox-Gastaut syndrome, and Epidiolex is expected to cost $ 32,500 annually, so investors plan to produce hundreds of millions of dollars in sales per year .

The commercial success of Epidiolex could however depend significantly on what is happening with Zogenix ZX008, a low-dose formulation of fenfluramine.

On July 12, Zogenix reported data from the second of two late-stage studies showing that ZX008-reduced seizures were 62.7% in patients with Dravet syndrome. The trial also showed that a significant proportion of ZX008 patients had achieved even larger reductions as a percentage of seizures. More specifically, nearly 36% of patients have seen their seizures decrease by 75% or more.

The results of a long-term phase 2 study of ZX008 in patients with Lennox-Gastaut syndrome were published in an industry journal in September. In this trial, the median reduction in seizures was 58% and 33% of patients experienced a seventy-five percent or more reduction in seizures.

SOURCE OF IMAGE: GETTY IMAGES.

Security could make a difference

It is unwise to compare the separate test data to determine if one drug is better than another, but it seems that ZX008 compares favorably with Epidiolex in these indications.

Zogenix's plan is to seek the FDA's approval in Dravet's syndrome in the fourth quarter. If the FDA agrees, it could challenge Epidiolex in terms of market share in 2019. A Phase 3 study on ZX008 is underway, and if the results corroborated the findings of Phase 2,

It remains to be seen which of these drugs captures the most shares in the treatment-resistant crisis market, but the winner may be dependent on the safety data.

In the case of Epidiolex, studies on elevated liver enzymes were of sufficient concern that the FDA could include a warning regarding the risk of liver injury on the Epidiolex label. As a result, Epidiolex patients should be tested for liver enzyme levels before using Epidiolex and then evaluated regularly during treatment to ensure that levels do not rise. In his trials, elevations of alanine aminotransferase (ALT) and / or aspartate aminotransferase (AST) were three times greater than the upper limit of normal in 13% of patients treated with Epidiolex but at only 1% of patients on placebo. Some Epidiolex patients have been hospitalized for treatment because of these elevations.

The security profile of the ZX008 is not necessarily perfect either. Fenfluramine is the "fen" part of the fen-phen obesity drug of the 1990s, which was discontinued as a result of the discovery that it could cause heart problems in patients.

Until now, there have been no cardiovascular problems seen with the use of ZX008, and this could suggest that the low dose Zogenix approach found the right point between safety and efficiency. In the trial on Dravet syndrome, "the incidence of serious adverse events was similar in the treated groups and placebo groups".

Nevertheless, it would not seem surprising that a potential approval by the FDA depends on cardiac monitoring.

What to look for next

The population of patients with Dravet syndrome is in the thousands, so the Lennox-Gastaut indication is more important commercially for these companies. As a result, investors will want to take a close look at Lennox-Gastaut's Phase 3 data as soon as it is available from Zogenix. If percentages reductions do not significantly decrease from phase 2 and security remains strong, this could be the biggest challenge for GW Pharmaceuticals' future sales in these indications.