Will Mirum Pharma Reverse Course?

(RTTNews) - Shares of Mirum Pharmaceuticals Inc. (MIRM) are down nearly 46% since their market debut on July 18, 2019.

Mirum Pharma is a biopharmaceutical company whose lead candidate, Maralixibat, is under clinical development for Alagille syndrome and progressive familial intrahepatic cholestasis.

Maralixibat works by inhibiting the apical sodium-dependent bile acid transporter (ASBT), which results in more bile acids being excreted in the feces, leading to lower levels of bile acids systemically, thereby reducing bile acid-mediated liver damage.

A phase III trial of Maralixibat, in pediatric patients with progressive familial intrahepatic cholestasis, dubbed MARCH-PFIC, was initiated in July of this year. This study is designed to enroll up to 30 patients aged one to 17 years, with topline results expected in the fourth quarter of 2020.

Progressive familial intrahepatic cholestasis (PFIC) is a disorder that causes progressive liver disease, which typically leads to liver failure. In people with PFIC, liver cells are less able to secrete a digestive fluid called bile. The buildup of bile in liver cells causes liver disease in affected individuals. (Source: NIH). This rare life-threatening disease affects approximately 3,000 in the United States and 5,000 in Europe.

The Company has completed a long-term phase IIb study of Maralixibat Alagille Syndrome, dubbed ICONIC. The study demonstrated that Maralixibat treatment led to profound and durable improvement in pruritis, xanthomas (lipid accumulation in the skin) and bile acids over 48 weeks.

Alagille syndrome, or ALGS, is a rare genetic disorder that can affect the liver, heart, and other parts of the body. One of the major features of Alagille syndrome is liver damage caused by abnormalities in the bile ducts. (Source: NIH). It is estimated that there are 9,000 cases of ALGS in the US, and 14,000 in Europe.

Mirum Pharma is in discussions with the FDA regarding the adequacy of the phase IIb data to support an NDA submission for Maralixibat for pruritus associated with ALGS. Meanwhile, a phase III study of Maralixibat in children with Alagille syndrome is planned for initiation in the first half of 2020.

The Company is also planning to explore Maralixibat in the indication of Biliary Atresia, a rare liver disorder.

The second drug candidate in Mirum Pharma's pipeline is Volixibat that is also designed to selectively inhibit ASBT, a protein that is primarily responsible for recycling bile acids from the intestine to the liver.

Volixibat is expected to move into phase II clinical trials in primary sclerosing cholangitis and intrahepatic cholestasis of pregnancy in 2020.

Primary sclerosing cholangitis (PSC) is a chronic, or long-term, disease that slowly damages the bile ducts. In patients with PSC, the bile ducts become blocked due to inflammation and scarring or fibrosis. (Source: American Liver Foundation).

Intrahepatic Cholestasis of Pregnancy (ICP) is a liver disorder that occurs in pregnant women, often during the third trimester, which impairs the normal release of bile from liver cells and leads to impaired liver function. It is estimated that each year there are approximately 40,000 cases of ICP in the United States and about 100,000 cases of ICP in Europe. ICP can lead to serious complications, including preterm labor and stillbirth.

Mirum Pharma went public on the Nasdaq Global Market on July 18, 2019, offering its shares at a price of $15 each. The stock has thus far hit a low of $7.10 and a high of $15.50.

MIRM closed Thursday's (Oct.31, 2019) trading at $7.18, down 3.23%.