September 1, 2010 (Vol. 30, No. 15)
Syamala Ariyanchira, Ph.D.
Emergence of MRSA Played a Huge Role in Reigniting Interest in This Medical Sector
Antibiotic resistance is now being recognized as a major health crisis that requires an intensely focused action plan. The antibiotic sector had been largely ignored for decades as pharmaceutical companies focused their research efforts on the lucrative chronic disease markets. Of late, however, the sector is witnessing renewed interest and investment, which are leading to much-needed innovation.
A recent report by BCC Research estimates that the global antibacterial market will grow from $42 billion in 2009 to $66 billion by 2014 at a compound average growth rate (CAGR) of 9.6%. Conventional antibiotics such as cephalosporins, fluoroquinolones, penicilins, and macrolids together account for 70% of the market, even though many of these classes are becoming ineffective against resistant strains.
Bacterial vaccines are also showing promising future growth trends. The BCC study estimates the value of the sector at $3.9 billion in 2009, accounting for 9% of the total market. Several new multivalent vaccines are in advanced stages of development. The bacterial vaccines sector is expected to grow at a CAGR of 31.6% to $15.5 billion by 2014.
The reasons for our current predicament are multifaceted. Over the years, several routes to fight bacteria have been explored and abandoned as bacteria have developed resistance to the treatments. The huge investment required to develop new antibiotic classes is often difficult to justify as the resistance issues often limit the long-term potential of new drugs. Moreover, efforts to contain antibiotic resistance can themselves limit the market potential of new antibiotics since new antibiotic classes are often prescribed cautiously.
There are a few antibacterials in the pipeline that may offer benefits over existing drugs. This is good news as immediate action plans are needed for the six pathogens collectively known as ESKAPE—Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species.
Revival of the Sector
The antibiotic resistance problem is being tackled through a number of new approaches. The Infectious Diseases Society of America (IDSA) advocates commercialization of 10 new antibiotics by 2020. In a June report titled “Antibiotic Resistance: Promoting Critically Needed Antibiotic Research and Development and Appropriate Use of these Prescription Drugs,” IDSA urges the U.S. government to introduce financial incentives that will encourage investment in antibiotic development projects.
New antibacterials in advanced stages of development are either analogs of existing antibiotic classes or innovative new classes of drugs and vaccines based on completely different approaches.
Cationic peptides represent an emerging class of antibacterials with good potential. Advantages of these peptides include broad-spectrum activity, rapid bactericidal activity, and lower potential for resistance development. Disadvantages include higher costs and limited stability, however, more stable and cost-effective synthetic peptides are also being developed.
An unconventional approach attracting a lot of attention lately is bacteriophage therapy. This approach was developed in Russia during World War II, but its development was stalled with the emergence of synthetic antibiotics. Currently, the treatment is approved for human use only in Georgia.
Bacterial interference, the practice of deliberately inoculating hosts with nonpathogenic bacteria, thus creating competition for nutrients and other requirements essential for the survival of pathogens, is another unconventional approach under investigation.
Many big pharma firms are bolstering their antibiotic pipelines through acquisitions and licensing agreements. Some of the recent licensing and acquisition activities related to the anti-infectives sector are listed in the Table.
Between 1970 and 1990, several broad-spectrum antibiotics entered the market. These drugs dovetailed nicely with the industry’s focus on blockbuster drugs. An emerging trend, however, is to move away from the heavy reliance on broad-spectrum antibiotics to narrow-spectrum antibiotics.
The rise of MRSA as a key public health concern has fueled interest in narrow-spectrum antibiotics. Currently, there are more than 20 products belonging to various antibiotic classes targeting MRSA in advanced stages of development.
The market created antibiotic resistance, but resistance is now creating new markets. Rising infections with Gram-negative pathogens have caused a revival in the use of old drugs such as colistin as well as rising investment in Gram-negative antibacterials development. The emerging trends presage an era of niche busters, with antibiotics targeting a particular class of pathogens or just one pathogen.