Chimerix's Brincidofovir Shows Potential Survival Benefit in Adenovirus Infection

DURHAM, N.C., Oct. 8, 2014 (GLOBE NEWSWIRE) -- Chimerix, Inc. (Nasdaq:CMRX), a biopharmaceutical company developing novel, oral antivirals in areas of high unmet medical need, announced today preliminary data for its investigational antiviral brincidofovir (BCV, CMX001) showing improved survival for patients with adenovirus in the open-label pilot portion of the Phase 3 AdVise Trial. These data will be presented at the annual meeting of the Infectious Diseases Society of America (IDSA), IDWeek, on Saturday, October 11 at 10:50 a.m. EDT in Philadelphia, PA.

The preliminary survival analysis data, based on 48 evaluable patients from the ongoing AdVise Trial, showed a mortality rate of 35 percent compared with the historic rates of up to 80 percent mortality in the first month after diagnosis. A majority of subjects also had suppression or clearance of adenovirus from the blood. There is currently no approved treatment for adenovirus, an infection that can progress rapidly in patients with a weakened immune system due to disease or medications.

"When progressive adenovirus infection occurs in immunocompromised patients, they deteriorate, and the infection can be fatal in up to four of every five cases," said Dr. Jo-Anne Young, Professor of Medicine and Medical Director of the Program in Transplant Infectious Disease at the University of Minnesota. "In these very sick patients who were treated with brincidofovir, nearly two-thirds of the patients survived the first few weeks when we have historically seen the highest mortality. These results are encouraging and warrant the continued evaluation of brincidofovir as a promising antiviral for this life-threatening infection, for which a treatment is desperately needed."

Chimerix initiated AdVise in March 2014 based on potency observed in vitro and on clinical data from a Phase 2 trial and a large expanded access trial which showed the potential for improved clinical outcomes. As of September 19th, 48 subjects had enrolled in AdVise, with 35 percent mortality observed to date (17 of 48) with a median duration of observation of 57 days for living patients.

The trial is enrolling pediatric and adult patients with adenovirus infection who receive brincidofovir twice weekly for twelve weeks. Baseline information and at least two months of follow up are available for 26 subjects. Of those 26 patients, 23 had measurable viral loads at study entry, and three patients had no virus detectable in the blood but had diagnosed adenovirus infection. Fourteen of the 23 patients with viremia at study entry achieved undetectable viral loads during treatment. Twelve of the 26 patients died.

Over half of the subjects were hematopoeitic cell transplant (HCT) recipients with disseminated disease, but solid organ transplant recipients and patients undergoing chemotherapy were also enrolled. Over one-third of the subjects (10 of 26) had a second active infection with another DNA virus in addition to adenovirus, including BK virus (27 percent), cytomegalovirus (19 percent) and Epstein Barr virus (8 percent).

The safety and tolerability profile of brincidofovir in these initial subjects was similar to other studies of brincidofovir in immunocompromised patients with complicated medical issues, with only three subjects discontinuing due to adverse events. Of the six subjects who enrolled in the study with adenovirus-related diarrhea, three reported improvement of symptoms and three remained stable.

"These data reinforce the potential for brincidofovir to significantly impact the mortality from adenovirus infections and provide data to support the design of the pivotal trial," said W. Garrett Nichols, M.D., M.S., Chief Medical Officer of Chimerix. "It is also important that, particularly in patients who are struggling with adenovirus infection, more than one-third of patients have more than one DNA virus, which underscores the need for a safe and broad-spectrum antiviral."

About AdVise

AdVise is a Phase 3 clinical trial to evaluate the safety and efficacy of brincidofovir for the treatment of adenovirus infection. In March 2014, Chimerix initiated the open-label pilot portion of the study. Chimerix is working closely with the U.S. Food and Drug Administration (FDA) on the design of a pivotal Phase 3 study that will be a continuation of this pilot study. Adenovirus infection can be associated with a mortality rate of up to 80 percent in patients who are undergoing hematopoeitic cell transplants (HCT), and there are no therapies approved to treat this infection. Adenovirus causes upper respiratory infections, including the common cold in individuals with a functional immune system, but it can lead to graft failure, severe pneumonia, hepatitis or death in those with a weakened immune system, such as patients who have undergone a transplant.

About Brincidofovir (BCV, CMX001)

Chimerix's lead product candidate, brincidofovir, is an oral nucleotide analog that has shown in vitro antiviral activity against all five families of DNA viruses that affect humans, including viruses in the herpes virus family and adenovirus. Brincidofovir has not been associated with kidney or bone marrow toxicity in nearly 900 patients treated to date, side effects that can be treatment limiting with currently available antivirals. Building on the positive Phase 2 results in cytomegalovirus (CMV) prevention, Chimerix initiated the Phase 3 SUPPRESS trial in 2013. If positive, data from SUPPRESS will support Chimerix's initial regulatory submission for brincidofovir for the prevention of CMV infection in adult hematopoietic cell transplant (HCT) recipients. Chimerix recently initiated AdVise, a Phase 3 trial in adenovirus, which is an often-fatal viral infection with no approved treatment; enrollment is ongoing for the pilot portion of the trial. Chimerix is also working with the Biomedical Advanced Research and Development Authority (BARDA) to develop brincidofovir as a medical countermeasure against smallpox. Brincidofovir has received Fast Track designation from the FDA for CMV, adenovirus, and smallpox.

About Chimerix

Chimerix is a biopharmaceutical company dedicated to discovering, developing and commercializing novel, oral antivirals in areas of high unmet medical need. Chimerix's proprietary technology has given rise to brincidofovir (BCV, CMX001), a clinical-stage nucleotide analog lipid-conjugate, which has demonstrated potent antiviral activity and safety in convenient, orally administered dosing regimens. Chimerix is currently enrolling SUPPRESS, the Phase 3 study of brincidofovir for the prevention of cytomegalovirus (CMV) in hematopoietic cell transplant recipients. In addition, Chimerix is enrolling the pilot portion of the Phase 3 AdVise study of brincidofovir for treatment of adenovirus infection. Chimerix is also working with BARDA to develop brincidofovir as a medical countermeasure against smallpox. For further information, please visit Chimerix's website,

Forward-Looking Statements

Statements contained in this press release regarding matters that are not historical facts are "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995. Because such statements are subject to risks and uncertainties, actual results may differ materially from those expressed or implied by such forward-looking statements. Risks are described more fully in Chimerix's filings with the Securities and Exchange Commission, including without limitation its most recent Quarterly Report on Form 10-Q, its most recently filed Current Reports on Form 8-K and other documents subsequently filed with or furnished to the Securities and Exchange Commission. All forward-looking statements contained in this press release speak only as of the date on which they were made. Chimerix undertakes no obligation to update such statements to reflect events that occur or circumstances that exist after the date on which they were made.

CONTACT: Joseph T. Schepers Executive Director, Investor Relations and Corporate Communications 919-287-4125Source:Chimerix, Inc.