Mirum Pharmaceuticals Presents Long-Term LIVMARLI® (maralixibat) Data and New Alagille Syndrome Caregiver Burden Analysis at NASPGHAN 2022 Annual Meeting

Rhea-AI Summary

Mirum Pharmaceuticals (NASDAQ: MIRM) showcased significant findings at the NASPGHAN Annual Meeting regarding maralixibat's long-term benefits for patients with Alagille syndrome (ALGS). Data presented highlighted a 70% reduction in clinical events over six years and substantial improvements in growth metrics over four years. Additionally, a multi-national analysis revealed significant caregiver impacts due to ALGS. The company continues to pursue further evaluations of maralixibat and plans a symposium on its clinical benefits.

Positive

• Maralixibat demonstrated a 70% reduction in clinical events over six years compared to historical data.
• Significant growth improvements were observed in ALGS patients treated with maralixibat over four years.
• The study on caregiver burden highlighted the unmet needs and challenges faced by families dealing with ALGS.

Negative

• Further analyses are necessary to fully understand the impact of maralixibat treatment on growth in ALGS patients.

- Six-year natural history comparison with maralixibat demonstrates event-free and transplant-free survival in patients with Alagille syndrome (ALGS)

- Characterization of four-year growth improvement in Alagille syndrome with maralixibat

- New analysis evaluating health-related quality of life impact assessed on caregivers of children with Alagille syndrome

- Mirum to host a scientific symposium on the clinical benefits of treating cholestasis in children

FOSTER CITY, Calif.--(BUSINESS WIRE)-- Mirum Pharmaceuticals, Inc. (NASDAQ: MIRM) shared data from three posters presented during the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition Annual Meeting (NASPGHAN) taking place October 12-16, 2022, in Orlando, Florida.

“Our presence at NASPGHAN provides an exciting opportunity for Mirum to showcase maralixibat six-year event-free survival benefit over the natural history standard of care, as well as long-term improvements in growth in patients with Alagille syndrome,” said Pam Vig, PhD, head of research and development at Mirum. “Further, while the burden of pruritus on patients with Alagille syndrome has been well-characterized through prior analyses, the impact to caregivers has been underappreciated, from mental health to financial distress.”

Scientific Symposium

The company will also host a scientific symposium: “Beyond Itch: Exploring the Clinical Benefits of Treating Cholestasis in Children,” featuring Drs. William F. Balistreri (chair), Regino P. Gonzalez-Peralta, Binita M. Kamath, and Saeed Mohammad.

The event will take place on Thursday, October 13, 2022, from 7:15-8:45pm ET in Sebastian L 1/2.

Presentations

The posters presented will be available within the Publications and Presentations section on Mirum’s website after they are presented at NASPGHAN.

Poster #290: Maralixibat Improves Growth in Patients with Alagille Syndrome: A 4-Year Analysis
Presented on Friday, October 14, 2022 – 12:00-2:30pm ET, Poster Session II
The analysis evaluated the impact of long-term maralixibat treatment on the growth and nutritional status of patients with ALGS, a disease for which patients typically present with significant growth deficits. Height and weight z-scores were evaluated in patients who participated in the maralixibat clinical studies and the long-term open-label extensions. The analysis included patients with ALGS who had both baseline and 204-week assessments for all eight parameters, and this group was divided into four subgroups based on height and weight z-score quartiles. No changes beyond standard of care in supplementation occurred during the study.

These data showed that patients with ALGS treated with long-term maralixibat (up to four years) had significantly increased height from baseline to week 204 (p=0.0004). Patients with the lowest height and weight z-scores at baseline had the greatest improvements in height and weight z-scores, and individuals that had the greatest catch-up weight gain also had the greatest catch-up height growth at week 48 (p=0.0013). The analysis also concluded that maralixibat-treated patients who achieved a serum bile acid threshold <200 µmol/L had greater accelerated height, suggesting bile acid homeostasis may facilitate improvement in height deficits. Further analyses, including comparison to natural history cohort of patients with ALGS, are needed to fully characterize the impact of maralixibat treatment on growth.

Poster #291: Maralixibat-Treated Patients with Alagille Syndrome Demonstrate Improved Event-Free Survival in a Natural History Comparison with Patients from the GALA Database: Application of Real-World Evidence Analytics
Presented on Friday, October 14, 2022 – 12:00-2:30pm ET, Poster Session II
The presentation reported on an analysis independently conducted and presented by Dr. Bettina Hansen and the Global Alagille Alliance (GALA) Study Group, which has aggregated the largest global natural history clinical database established for ALGS. The analysis evaluated time to first clinical event using six years of follow-up data from pooled ALGS maralixibat studies (n=84) and compared it against an external natural history control cohort from the GALA clinical database. Events were defined as liver transplantation, biliary diversion surgery, decompensation events (ascites requiring therapy or variceal bleeding), or death. Additional analyses included transplant-free survival as well as several sensitivity and subgroup analyses to confirm robustness of the findings.

The analysis demonstrated a highly significant improvement in six-year event-free survival with a p-value of <0.0001 (HR: 0.305, 95% CI: 0.189-0.491) translating to a 70% overall reduction for clinical outcomes with maralixibat. The analysis also showed highly statistically significant improvements in transplant-free survival with a p-value of <0.0001 (HR: 0.332, 95% CI: 0.197-0.559).

Poster #552: Caregiver Burden Associated with Caring for a Child with Alagille Syndrome: A Multi-National Quantitative Analysis
Presented on Saturday, October 15, 2022 – 12:00-2:30pm ET
Pruritus is the most common and debilitating symptom of ALGS, occurring in 80% of patients. While the impact to patients has been assessed, the burden on caregivers is thought to have a significant negative impact on their quality of life. The analysis is the first comprehensive, multinational study conducted to better understand and characterize the impact of ALGS on caregivers’ sleep, work productivity, financial wellness, and mental health. The survey used demographic, clinical and health-related quality of life questions in 180 participants (90 in the ALGS caregiver population and 90 in the matched control group population).

The survey data showed that a caregiver for a child with ALGS typically misses seven hours of paid work per week and 60% of caregivers reported changing, reducing, or stopping employment altogether. 73% of all caregivers reported that their sleep was negatively impacted in a usual week.

Finally, a higher proportion of caregivers of children with ALGS had moderate-to-severe anxiety and depression compared with UK general population norms.

These data demonstrate that the impact of pruritus extends beyond the patient and can have a significant effect on people caring for a child with ALGS with added emotional, health, and economic stress.

About LIVMARLI® (maralixibat) oral solution

LIVMARLI® (maralixibat) oral solution is an orally administered, once-daily, ileal bile acid transporter (IBAT) inhibitor approved by the U.S. Food and Drug Administration for the treatment of cholestatic pruritus in patients with Alagille syndrome (ALGS) one year of age and older and is the only FDA-approved medication to treat cholestatic pruritus associated with Alagille syndrome. For more information, please visit LIVMARLI.com.

LIVMARLI is currently being evaluated in late-stage clinical studies in other rare cholestatic liver diseases including progressive familial intrahepatic cholestasis (PFIC) and biliary atresia. LIVMARLI has received Breakthrough Therapy designation for ALGS and PFIC type 2 and orphan designation for ALGS, PFIC and biliary atresia. To learn more about ongoing clinical trials with LIVMARLI, please visit Mirum’s clinical trials section on the company’s website.

IMPORTANT SAFETY INFORMATION

LIVMARLI can cause side effects, including:

Changes in liver tests. Changes in certain liver tests are common in patients with Alagille syndrome and can worsen during treatment with LIVMARLI. These changes may be a sign of liver injury and can be serious. Your healthcare provider should do blood tests before starting and during treatment to check your liver function. Tell your healthcare provider right away if you get any signs or symptoms of liver problems, including nausea or vomiting, skin or the white part of the eye turns yellow, dark or brown urine, pain on the right side of the stomach (abdomen) or loss of appetite.

Stomach and intestinal (gastrointestinal) problems. LIVMARLI can cause stomach and intestinal problems, including diarrhea, stomach pain, and vomiting during treatment. Tell your healthcare provider right away if you have any of these symptoms more often or more severely than normal for you.

A condition called Fat Soluble Vitamin (FSV) Deficiency caused by low levels of certain vitamins (vitamin A, D, E, and K) stored in body fat. FSV deficiency is common in patients with Alagille syndrome but may worsen during treatment. Your healthcare provider should do blood tests before starting and during treatment.

Other common side effects reported during treatment were bone fractures and gastrointestinal bleeding.

Prescribing Information

About Mirum Pharmaceuticals, Inc.

Mirum Pharmaceuticals, Inc. is a biopharmaceutical company dedicated to transforming the treatment of rare diseases. Mirum’s approved medication is LIVMARLI® (maralixibat) oral solution which is approved in the U.S. for the treatment of cholestatic pruritus in patients with Alagille syndrome one year of age and older. Please view the warnings and precautions available in the Prescribing information or, for more information, visit LIVMARLI.com.

Mirum’s late-stage pipeline includes two investigational treatments for debilitating liver diseases affecting children and adults. Maralixibat (LIVMARLI), an oral ileal bile acid transporter (IBAT) inhibitor, is currently being evaluated in clinical trials for pediatric liver diseases and includes the MARCH Phase 3 study for progressive familial intrahepatic cholestasis (PFIC) and the EMBARK Phase 2b study for patients with biliary atresia. In addition, Mirum has an expanded access program open across multiple countries for eligible patients with ALGS and PFIC.

Mirum has submitted a Marketing Authorization Application to the European Medicines Agency for maralixibat for the treatment of cholestatic liver disease in patients with Alagille syndrome.

Mirum’s second investigational treatment, volixibat, an oral IBAT inhibitor, is being evaluated in three potentially registrational studies including the VISTAS Phase 2b clinical trial for adults with primary sclerosing cholangitis, the OHANA Phase 2b clinical trial for pregnant women with intrahepatic cholestasis of pregnancy, and the VANTAGE Phase 2b clinical trial for adults with primary biliary cholangitis.

Learn more about Mirum by visiting www.mirumpharma.com. Follow Mirum on Twitter, Facebook, LinkedIn and Instagram.

Forward-Looking Statements

This press release includes forward-looking statements pertaining to the Company’s planned participation at a scientific conference, including data presentation title and synopsis, which may include discussion of the Company’s clinical and research data, including the discovery, development, and commercialization of our product candidates and technologies, and the therapeutic potential thereof, the continuation of our clinical trials, and the success of our collaborations with partners and any potential future collaborations. Such forward-looking statements are subject to risks and uncertainties that could cause actual results to differ materially from those expressed or implied in such statements. Applicable risks and uncertainties include those relating to our preclinical research and clinical programs and other risks and uncertainties that could cause actual results to differ materially from those expressed or implied in such statements. Applicable risks and uncertainties include those relating to our preclinical research and clinical programs and other risks identified under the heading “Risk Factors” included in our most recent Form 10-Q and Form 10-K filings and in other future filings with the SEC. The forward-looking statements contained in this press release reflect Mirum’s current views with respect to future events, and Mirum does not undertake and specifically disclaims any obligation to update any forward-looking statements, except as required by law.

View source version on businesswire.com: https://www.businesswire.com/news/home/20221012005501/en/

Media Contact:

Erin Murphy

media@mirumpharma.com

Investor Contacts:

Ian Clements, Ph.D.

ir@mirumpharma.com

Sam Martin

Argot Partners

ir@mirumpharma.com

Source: Mirum Pharmaceuticals, Inc.

FAQ

What were the key findings of Mirum Pharmaceuticals at the NASPGHAN meeting regarding MIRM?

Mirum Pharmaceuticals reported a 70% reduction in clinical events for ALGS patients treated with maralixibat over six years.

What impact does maralixibat have on growth in Alagille syndrome?

Maralixibat treatment led to significant height and weight improvements in ALGS patients over a four-year period.

What did the caregiver burden analysis reveal about Alagille syndrome patients?

The analysis showed that caregivers experience significant mental health and financial distress due to the care demands of children with ALGS.

When is Mirum hosting a symposium on cholestasis treatment?

The scientific symposium will take place on October 13, 2022, during the NASPGHAN Annual Meeting.