ROCKVILLE, Md., Feb. 7 /PRNewswire-FirstCall/ -- Nabi Biopharmaceuticals today provided an update on the development of its Gram- positive infections program, which includes several product candidates for the prevention and treatment of S. aureus, S. epidermidis and enterococcal infections. Together these bacteria account for two-thirds of healthcare- associated infections reported annually.
Nabi Biopharmaceuticals announced positive data from Phase I studies of the company's S. epidermidis PS-1 vaccine and its S. aureus Type 336 vaccine. Both Phase I studies evaluated the safety and immune response of these vaccines in healthy volunteers. The data support that escalating doses of the vaccines were well tolerated and resulted in significant dose-related increases in levels of antibodies against S. epidermidis PS-1 and S. aureus Type 336. The results of these studies also support the company's conjugation technology in stimulating antibody responses. High antibody titers against specific targets are critical in conferring protection to patients against these infections.
Thomas H. McLain, chairman, chief executive officer and president, Nabi Biopharmaceuticals, stated, "Clinically, Nabi Biopharmaceuticals is focused on addressing a large, unmet medical need. Collectively, S. epidermidis and S. aureus represent approximately 80 percent of all Gram-positive hospital- acquired bacterial infections. Commercially, we are focused on developing products that address a large, underserved market. It is estimated that by 2008 the market for new hospital anti-bacterial products will reach $10.1 billion. Our product, growth and business strategies remain aligned with global trends and policies that have defined the critical need for effective and cost-efficient treatments and preventative solutions. In this way, Nabi Biopharmaceuticals is uniquely and strategically positioned to capitalize on its technology and expertise to develop a portfolio of vaccines and antibody products via our own resources and, when appropriate, with strategic partners."
These results and the direction of the company's Gram-positive program are important for several reasons, including the clinical and commercial potential of vaccines to prevent S. epidermidis and S. aureus infections, as well as antibody and other innovative approaches that Nabi Biopharmaceuticals plans to develop products to treat and prevent these infections:
The Clinical and Economic Challenges
S. epidermidis and S. aureus are Prevalent and Resistant to Antibiotics. Current preventative and treatment approaches fall short of adequately addressing S. epidermidis and S. aureus infections, which are increasingly becoming resistant to antibiotics. These bacteria often live transiently or permanently in the nasal passages or on the skin of humans; and can spread to the blood through breaks in the nasal membranes or skin.
S. aureus and S. epidermidis infections are prevalent in hospitals and account for the majority of bloodstream infections. There are approximately 2.6 to 2.8 million hospital-associated infections reported annually. The mean cost is estimated at $13,973 per infection or a range of $36.3 - $39.1 billion annually. The estimated overall mortality rate associated with hospital- associated (nosocomial) bloodstream infections and pneumonia are 23.8 percent to 50 percent and 14.8 percent to 71 percent, respectively.
It is estimated that healthcare-associated treatment costs associated with S. epidermidis infections total almost $600 million each year. To add to the economic burden, methicillin-resistant S. epidermidis (MRSE) rates have reached approximately 80 percent, and over 50 percent of S. epidermidis infections are also resistant to other currently administered anti-microbials. Associated S. epidermidis mortality rates total over 20 percent.
Type 336 accounts for approximately 20 percent of S. aureus infections that do not form a polysaccharide capsule in the human bloodstream. In addition, another 30 percent of S. aureus bacteria are partially encapsulated and Type 336 may also have benefit in preventing and treating infections caused by those bacteria. Since its initial identification in the 1960s, hospital-associated methicillin-resistant S. aureus (MRSA) rates have climbed to 57 percent in the ICU and to over 40 percent in non-ICU in-patient settings by 2002. It is estimated that over 30 percent of the adult population at any given time are colonized with S. aureus.
A Multi-faceted Solution
Both vaccines are the first-of-their kind in development to prevent S. epidermidis and S. aureus Type 336 in patients, including those undergoing certain types of invasive surgery, patients in intensive care or shock-trauma units, patients receiving cancer chemotherapy or other immune suppressive treatments, dialysis patients and patients in long-term care facilities.
The PS-1 antigen is found on approximately 60 to 70 percent of all S. epidermidis strains. Immunization with PS-1 results in the production of antibodies that attack a cell wall structure of the bacteria. The mechanism of action of the Type 336 vaccine is independent of the polysaccharide capsule targeted by the company's S. aureus Types 5 and 8 vaccine approach, in that it attacks a structure in the cell wall of the bacteria, not the polysaccharide capsule outside the cell wall. Our research indicates that what we target in S. aureus Type 336 is cross-reactive to S. epidermidis. As an example, data already support that Type 336 antibodies are cross reactive with the majority of S. epidermidis bacteria. The results announced today clearly support moving these programs into Phase II clinical testing.
Raafat E.F. Fahim, Ph.D., senior vice president research, technical and production operations, Nabi Biopharmaceuticals, stated, "Nabi Biopharmaceuticals' R&D pipeline is deep as we plan to develop several unique approaches to Gram-positive infections. In addition to the capsular and non- capsular approaches to S. aureus and the proprietary targets to S. epidermidis, we are also developing novel vaccines and antibody products to enterococci, community-acquired MRSA, as well as anti-infective approaches to nasal colonization, skin and soft tissue Staph infections."
Dr. Fahim continued, "We are also fortunate to have the manufacturing capabilities to produce these vaccines and antibody products in our own Boca Raton facilities."
Upcoming Milestones
During 2006, the company will further study these vaccine candidates as stimulating agents to produce antibody products active against these dangerous bacteria. Antibodies can be used for prevention in patients at immediate risk for infection and may act synergistically with antibiotics in the treatment of active infections.
Based on the Phase I clinical trial results announced today and the potential to develop these vaccines and antibodies in a variety of ways, Nabi Biopharmaceuticals will advance its S. epidermidis PS-1 and S. aureus Type 336 programs into a Phase II clinical trial designed as a "proof-of-concept" study. The company expects to initiate this clinical trial in the first half of 2007 and it will evaluate the benefit of a multi-valent product in reducing or treating infection in patient populations at-risk for infection. The company will work with its Gram-positive infections advisory panel to both define the study population and advise whether the vaccine or antibody product should first advance into late-stage clinical study. Based on the outcome of the StaphVAX(R) [Staphylococcus aureus Polysaccharide Conjugate Vaccine] assessment, this trial may or may not involve combination with capsular polysaccharide Types 5 and 8. Nabi Biopharmaceuticals anticipates that the next trial will be conducted in both U.S. and EU sites.
About the S. epidermidis PS-I Study
The S. epidermidis PS-I Phase I study was a double-blinded, placebo- controlled study evaluating safety and antibody responses of the vaccine in 36 patients at three different dosage levels. Within each of these three dose groups there were 12 patients, nine receiving the S. epidermidis vaccine and three receiving placebo. The doses were administered in an escalating manner.
About the Type 336 Study
The Type 336 Phase I study was a double-blinded, placebo-controlled study evaluating safety and antibody responses of the vaccine in 48 patients at four different dosage levels. Within each of these four dose groups there were 12 patients, nine receiving the Type 336 vaccine and three receiving placebo. The doses were administered in an escalating manner.
Henrik S. Rasmussen, M.D., Ph.D., senior vice president, clinical, medical and regulatory affairs, Nabi Biopharmaceuticals, stated, "A growing number of patients, such as patients with indwelling catheters, patients in intensive care units, patients receiving cancer chemotherapy, surgical patients receiving implantation of various devices, dialysis patients and premature babies, develop staphylococcus bacterial infections, either S. aureus or S. epidermidis. To add to this problem, these bacteria are becoming increasingly resistant to a number of different antibiotics. As a result, S. aureus and S. epidermidis infections often lead to severe illness and death. Consequently, new and more effective solutions, such as vaccines and antibodies, are urgently needed."
Mr. McLain concluded, "Our Gram-positive infections program is robust, and aligned with the company's business strategy to develop clinically relevant, efficacious and cost-effective products in areas of significant unmet medical need. We are pleased with today's S. aureus Type 336 and S. epidermidis PS-1 results, as they support our strategic approach in advancing our Gram-positive infections program. This approach would be combined with our S. aureus Types 5 and 8 program to develop a next generation product, if the outcome of our ongoing assessment is positive."
The company also announced that progress continues in its investigation of results from a recent Phase III study of its S. aureus Types 5 and 8 vaccine candidate, StaphVAX. The company confirmed that it expects to review the results of the investigation with its outside advisory panel and define plans for this element of its Gram-positive infections program in the first half of 2006.
About Nabi Biopharmaceuticals
Nabi Biopharmaceuticals leverages its experience and knowledge in powering the immune system to develop and market products that fight serious medical conditions. We are focusing on developing products addressing commercial opportunities in our core business areas: Gram-positive bacterial infections, hepatitis, kidney disease (nephrology), and nicotine addiction. We have three products on the market today: PhosLo(R) (calcium acetate), Nabi-HB(R) [Hepatitis B Immune Globulin (Human)], and Aloprim(TM) [Allopurinol sodium (for injection)] and a number of products in various stages of clinical and pre-clinical development. The company also filed Marketing Authorization Applications (MAA) in Europe to market Nabi-HB(R) Intravenous [Hepatitis B Immune Globulin (Human) Intravenous] under the trade name HEBIG(TM) for the prevention of hepatitis B disease in HBV-positive liver transplant patients; and for PhosLo, which is already marketed in the United States. The company's products in development include NicVAX(TM) (Nicotine Conjugate Vaccine), a vaccine to treat nicotine addiction, and Civacir(TM) [Hepatitis C Immune Globulin (Human)], an antibody for preventing hepatitis C virus re-infection in liver transplant patients. For additional information on Nabi Biopharmaceuticals, please visit our website: http://www.nabi.com .
This press release contains forward-looking statements that reflect the company's current expectations regarding future events. Any such forward- looking statements are not guarantees of future performance and involve significant risks and uncertainties. Actual results may differ significantly from those in the forward-looking statements as a result of any number of factors, including, but not limited to risks relating to the company's ability to: advance the development of products currently in the pipeline or in clinical trials; complete the assessment of the StaphVAX Phase III clinical trials during the first half of 2006; maintain the human and financial resources to commercialize current products and bring to market products in development; obtain regulatory approval for its products in the U.S. or other markets; successfully develop manufacture and market its products; utilize the full capacity of its manufacturing facility; realize the value of its acquisition of PhosLo; realize sales from Nabi-HB due to patient treatment protocols and the number of liver transplants performed in HBV-positive patients; realize the value from its vaccine manufacturing facility; realize future sales growth for its biopharmaceutical products; prevail in patent litigation; raise additional capital on acceptable terms; re-pay its outstanding convertible senior notes when due; and the company's dependence upon: third parties to manufacture its products and a small number of customers. Many of these factors are more fully discussed, as are other factors, in the company's Annual Report on Form 10-K for the fiscal year ended December 25, 2004 filed with the Securities and Exchange Commission.
Nabi BiopharmaceuticalsCONTACT: Thomas E. Rathjen, Vice President, Investor Relations, NabiBiopharmaceuticals, +1-561-989-5800
Web site: http://www.nabi.com/
