FDA approves treatment for Clostridium difficile infection

The U.S. Food and Drug Administration today approved Dificid (fidaxomicin) tablets for the treatment of Clostridium difficile-associated diarrhea (CDAD).

Clostridium difficile (C. difficile) is a bacterium that can cause diarrhea and lead to colitis, other serious intestinal conditions, and death in severe cases. C. difficile bacteria are found in the stool of an infected person, and others can become infected if they touch items or surfaces contaminated with the bacteria or spores and then touch their mouths.

The safety and efficacy of Dificid were demonstrated in two trials that included 564 patients with CDAD that compared Dificid with vancomycin, a common antibiotic used to treat CDAD. The clinical response was similar in the Dificid group compared with the vancomycin group in both studies. In some patients with CDAD, symptoms can return. In the Dificid trials, a greater number of patients treated with Dificid had a sustained cure three weeks after treatment ended versus those patients treated with vancomycin.

“In recent years, many in the infectious disease community have seen an increase in the number of cases of people with a C. difficile infection,” said Edward Cox, M.D., M.P.H., director of the Office of Antimicrobial Products in the FDA’s Center for Drug Evaluation and Research. “Dificid is an effective new treatment option for patients who develop Clostridium difficile-associated diarrhea.”

Dificid, a macrolide antibacterial, should be taken two times a day for 10 days with or without food.

To maintain the effectiveness of Dificid, and to reduce the development of drug-resistant bacteria, the drug should be used only to treat infections that are proven or strongly suspected to be caused by C. difficile.

The most common side effects reported with Dificid included nausea, vomiting, headache, abdominal pain, and diarrhea.

People at risk of developing the bacterial infection include the elderly, patients in hospitals or nursing homes, and people taking antibiotics for another infection. The most effective way to prevent CDAD is thorough handwashing with soap and warm water.

Dificid was developed by San Diego-based Optimer Pharmaceuticals Inc.

-----

Community News You Can Use
Click to read MORE news:
www.GeorgiaFrontPage.com
Twitter: @gafrontpage & @TheGATable @HookedonHistory
www.ArtsAcrossGeorgia.com
Twitter: @artsacrossga, @softnblue, @RimbomboAAG @FayetteFP

FDA permits marketing of first test for most common cause of gastroenteritis outbreaks

The U.S. Food and Drug Administration allowed marketing of the first test for the preliminary identification of norovirus.

The Ridascreen Norovirus 3rd Generation EIA assay is for use when a number of people have simultaneously contracted gastroenteritis and there is a clear avenue for virus transmission, such as a shared location or food.

Norovirus is a leading cause of food-borne disease outbreaks in the United States.

Acute gastroenteritis is an inflammation of the stomach and intestine that can cause diarrhea, vomiting and stomach pain. Norovirus contamination usually occurs in settings where there is close group contact, such as cruise ships, hospitals, long-term care facilities, and schools or child-care centers. It is a highly contagious virus that spreads rapidly through direct person-to-person contact, contaminated food or water, and by touching contaminated surfaces.

“This test provides an avenue for early identification of norovirus,” said Jeffrey Shuren, M.D., J.D., director of the FDA’s Center for Devices and Radiological Health. “Early intervention can halt the spread of an outbreak.”

The test is not sensitive enough for use when only a single person has symptoms and should not be used for diagnosing individual patients.

The manufacturer demonstrated the performance of the Ridascreen test by comparing results of it to the results of a norovirus reference standard for 609 fecal samples. When the fecal samples were tested with Ridascreen, overall results on average were less sensitive than those of standard reference tests, detecting norovirus across samples about 2/3 of the time it was present.

The FDA reviewed data for Ridascreen via the de novo pathway, an alternative path to market for devices that are lower risk and may not require premarket approval (PMA), but are of a new type, and therefore may not be able to be cleared in a '510(k)' premarket notification.

In March, the U.S. Centers for Disease Control and Prevention will be updating management and disease prevention guidelines for norovirus outbreaks. These guidelines will likely reflect substantial advances made in norovirus epidemiology, immunology, diagnostic methods and infection control.

Ridascreen is made by R-Biopharm AG, located in Darmstadt, Germany.

-----
Community News You Can Use
Click to read MORE news:
www.GeorgiaFrontPage.com
Twitter: @gafrontpage & @TheGATable @HookedonHistory
www.ArtsAcrossGeorgia.com
Twitter: @artsacrossga, @softnblue, @RimbomboAAG @FayetteFP

New Low-Cost Method to Deliver Vaccine Shows Promise

/PRNewswire/ -- Researchers have developed a promising new approach to vaccination for rotavirus, a common cause of severe diarrheal disease that is responsible for approximately 500,000 deaths among children in the developing world every year. In a study published in the November issue of Clinical and Vaccine Immunology, a vaccine delivered as nasal drops effectively induced an immune response in mice and protected them from rotavirus infection. The new vaccine delivery system has also been tested successfully and found to be heat stable with tetanus and is currently being tested with diphtheria and pertussis.

The team from the Cummings School of Veterinary Medicine at Tufts University and Tufts University School of Medicine collaborated with researchers from Boston and Tulane Universities to test the effectiveness of immunization with harmless bacteria that were engineered to display rotavirus protein.

"The new vaccine, in conjunction with an agent that enhances immunity, induced sufficient antibody formation against rotavirus to protect mice against infection when the mice were exposed to rotavirus three weeks after their third immunization," explained John E. Herrmann, Ph.D., research professor in the infectious diseases division of the department of biomedical sciences at the Cummings School of Veterinary Medicine at Tufts University and the senior author of the published study.

"We created the rotavirus vaccine using a harmless bacterium called Bacillus subtilis (B. subtilis), which we can modify to display on its surface or in its cytoplasm proteins from infectious bacteria and viruses. When people are exposed to these proteins, they develop antibodies against them and therefore become immune to the bacteria and viruses," said the study's first author Sangun Lee, Ph.D., DVM, research associate at the Cummings School. "The B. subtilis bacteria are so harmless that they are part of the normal diet in several Asian countries."

"The vaccine with the Bacillus bacteria is very inexpensive to produce in large quantities and, unlike most traditional vaccines, requires no special purification steps before use. As a result, the cost of vaccine production is unusually low," explained Saul Tzipori, BVSc (DVM), DSc, Ph.D., Agnes Varis University Chair in Science and Society, distinguished professor of microbiology and infectious diseases, and director of the infectious diseases division of the department of biomedical sciences at the Cummings School. These findings are consistent with the team's previous studies in which they demonstrated that B. subtilis bacteria displaying a fragment of tetanus toxin protein completely protect mice from tetanus. Tetanus vaccines have been stored for more than a year at 113(o)F without any loss of potency, a property that may be common to all B. subtilis vaccines.

Vaccines currently available have to be stored in refrigerators or freezers until the moment they are administered. This cold chain is difficult and costly to maintain. In many parts of the world, there is insufficient refrigeration or electricity to keep vaccines cold. The lack of refrigeration combined with the lack of trained personnel, especially in rural areas in developing countries, make it impossible for many children and adults to be vaccinated against standard infections, such as tetanus, rotavirus, diphtheria, pertussis (whooping cough) and other diseases.

"In addition to being heat-stable and low-cost, the B. subtilis vaccines are given in the form of nasal drops or spray. A needle-free approach to vaccination is particularly advantageous in developing countries where clean needles and syringes and trained personnel are not always available," said team leader Abraham L. (Linc) Sonenshein, Ph.D., professor and acting chair of molecular biology and microbiology at TUSM and member of the genetics and microbiology program faculties at the Sackler School of Graduate Biomedical Sciences at Tufts.

"This vaccine project is still in the developmental stage," he continued. "The next major step for these vaccines is to show that they are safe and work well in humans, and then to extend the rotavirus and tetanus vaccine technology to include diphtheria, pertussis and other infectious diseases. Those diseases cause tens of thousands of deaths, particularly in newborns and in South-East Asia. We are actively looking for partners in the U.S. and around the world to help us pursue our goal of reaching the point where many childhood and adult vaccines can be manufactured in a way that avoids the need for injection or refrigeration. Jerry Keusch of Boston University School of Public Health and I started this project 15 years ago, and it has taken a long time to reach the stage where we now have effective needle-free vaccines. The technology has now advanced enough that we can expect to be successful with many other vaccines in a short time frame."

Additional authors include Boris R. Belitsky, Ph.D., assistant research professor in the department of molecular biology and microbiology at TUSM; James P. Brinker, M.P.H, in the department of biomedical sciences at the Cummings School; Kathryn O. Kerstein, MS, senior research associate in the department of molecular biology and microbiology at TUSM; David W. Brown, Ph.D., DVM, clinical assistant professor in the infectious diseases division of the department of biomedical sciences at the Cummings School; Gerald T. Keusch, MD, professor in the department of international health at Boston University School of Public Health, professor of medicine at Boston University School of Medicine and U.S. chairman of the Indo-U.S. Vaccine Action Program at the National Institutes of Health; and John D. Clements, Ph.D., professor and chair of the department of microbiology and immunology at Tulane University Health Sciences Center.

This study was supported by a grant from the Grand Challenges in Global Health program of the Bill and Melinda Gates Foundation, and this grant was administered by the Foundation for the National Institutes of Health. Patent applications related to the discoveries reported in these studies have been filed by Tufts University.

Lee S, Belitsky BR, Brinker JP, Kerstein KO, Brown DW, Clements JD, Keusch GT, Tzipori S, Sonenshein AL, Herrmann JE. Clinical and Vaccine Immunology.. 2010 (November); 17 (11): 1647-1655. "Development of a Bacillus subtilis-based rotavirus vaccine." DOI: 10.1128/CVI/00135-10.

Lee S, Belitsky BR, Brown DW, Brinker JP, Kerstein KO, Herrmann JE, Keusch GT, Sonenshein AL, Tzipori S. Vaccine. 2010 (September 24); 28 (41), 6658-6665. "Efficacy, heat stability and safety of intranasally administered Bacillus subtilis spore or vegetative cell vaccines expressing tetanus toxin fragment C." DOI:10.1016/j.vaccine.2010.08.016.

-----
Community News You Can Use
Click to read MORE news:
www.GeorgiaFrontPage.com
Twitter: @gafrontpage & @TheGATable @HookedonHistory
www.ArtsAcrossGeorgia.com
Twitter: @artsacrossga, @softnblue, @RimbomboAAG
www.FayetteFrontPage.com
Twitter: @FayetteFP

FDA Approves New Use of Xifaxan for Patients with Liver Disease

The U.S. Food and Drug Administration today approved the use of Xifaxan for reduction in the risk of the recurrence of overt hepatic encephalopathy (HE) in patients with advanced liver disease. This is a new use for Xifaxan (rifaximin), a drug that has been approved for the treatment of traveler’s diarrhea.

Hepatic encephalopathy is a worsening of brain function that can occur in patients whose liver can no longer remove toxins from the blood. Increased levels of ammonia in the blood are thought to play a role in the development of HE, and Xifaxan works by reducing these levels.

“The approval of Xifaxan for this new indication provides an additional treatment option for patients with liver disease,” said Joyce Korvick, M.D., deputy director for safety of FDA’s Division of Gastroenterology Products. “Hepatic encephalopathy occurs commonly in patients with liver disease, and there are few effective treatments for this serious condition.”

The efficacy of Xifaxan was established in a randomized placebo-controlled clinical trial of adult patients from the United States, Canada, and Russia. Patients with liver disease who entered the trial had no or mild symptoms of HE. Patients treated with Xifaxan were less likely to develop HE during the trial, compared to placebo-treated patients.

Xifaxan was not studied in patients with the most severe forms of liver disease. Since most patients were also taking lactulose (a synthetic sugar which helps prevent absorption of ammonia from the intestine) during the trial, the efficacy of Xifaxan as a stand-alone treatment for HE could not be assessed.

The most common adverse reactions reported with the use of Xifaxan in patients with liver disease include swelling of the arms and legs (peripheral edema), nausea, gas, and headache.

Xifaxan received a priority review under FDA’s new drug application process and was granted orphan designation status. Xifaxan is manufactured by Salix Pharmaceuticals Inc. of Morrisville, N.C.

-----
www.fayettefrontpage.com
Fayette Front Page
www.georgiafrontpage.com
Georgia Front Page
Follow us on Twitter:  @GAFrontPage

Unusual Rotavirus Season May Be Due to Newly Introduced Vaccine

Rotavirus activity in the ongoing 2007-2008 season appears to have started later than usual and have been less severe than during any of the previous seasons for which data are available, according to an interim report issued in today's early release edition of the Centers for Disease Control and Prevention's Morbidity and Mortality Weekly Report (MMWR).

Rotavirus is the leading cause of severe gastroenteritis (vomiting and diarrhea) in infants and young children, annually causing about 410,000 physician office visits, 205,000-272,000 emergency department visits, 55,000-70,000 hospitalizations, and between 20 and 60 deaths among US children less than 5 years of age. Worldwide, rotavirus causes approximately 1,600 deaths each day among children less than 5 years of age.

Data from around the United States indicate that during the ongoing season, rotavirus activity was delayed by about three months compared with the start time for the previous 15 years. The season began at the end of February instead of November, the usual start time, and the season peaked at the end of April instead of March, the usual peak time.

Hospitalizations, emergency department visits, and physician visits were also substantially reduced at some network of medical centers conducting prospective rotavirus surveillance. The number of laboratory tests performed for rotavirus from Jan. 1 to May 3, 2008, was 37 percent lower than usual, and the percent of all tests conducted for gastroenteritis that were positive for rotavirus was 79 percent lower than usual.

The report indicates that marked changes in rotavirus activity may be due to a newly introduced rotavirus vaccine for infants. In 2006, a new rotavirus vaccine, RotaTeq (Merck & Co. Inc.), was recommended for routine immunization of U.S. infants at 2, 4 and 6 months of age. Clinical trial results indicated that this live, oral vaccine prevented 74 percent of all rotavirus cases, about 98 percent of severe cases, and about 96 percent of hospitalizations due to rotavirus.

"The changes appear to be greater than expected based on the protective effects of the vaccine alone," said Dr. Anne Schuchat, director of the National Center for Immunization and Respiratory Diseases at CDC. "It is also possible that current levels of vaccination may be helping to decrease the spread of rotavirus to unvaccinated individuals in the community. Ongoing monitoring is needed to confirm the impact of vaccination this year and to monitor the impact of the vaccine on rotavirus disease and its epidemiology over time."

The data used in the new report were obtained from the National Respiratory and Enteric Virus Surveillance System (NREVSS) and from the New Vaccine Surveillance Network (NVSN). NREVSS is a voluntary network of U.S. laboratories that provide CDC with weekly reports of the number of tests performed and positive results obtained for a variety of
pathogens, including rotavirus.

Rotavirus is highly contagious. Large amounts of the virus are shed in the stool of infected persons and can be spread by contaminated hands and objects. Children can spread rotavirus both before and after they become sick with diarrhea, and they can pass the virus to household
members and other close contacts.