The Silver Age of Antibiotics

By: Andrew Leong, Staff Writer

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This year, the FDA approved three new antibiotics to treat acute bacterial skin and skin structure infections (ABSSSI) caused by Staphylococcus aureus, including MRSA. They are dalbavancin (Dalvance^TM), tedizolid phosphate (Sivextro^TM), and oritavancin (Orbactiv^TM). Dalbavancin was approved on May 23, 2014 and is administered intravenously in two doses (1000 mg, 500 mg), one week apart.¹ Tedizolid phosphate was approved on June 20, 2014 and is administered intravenously as a 200 mg dose once daily for six days. It is also available orally as a 200 mg dose.² Oritavancin was approved on August 6, 2014 and is administered intravenously in a single 1200 mg dose.³

The consecutive approvals of these antibiotics represent the federal government’s proactive effort in the battle against resistant strains of bacteria. Nearly half of the antibiotics used today were discovered during the 1930’s to the 1960’s.^4,5 It was thought that this “golden age of antibiotics” would combat all infectious diseases. Unfortunately, this is not the case today.

The problem of antibiotic resistance stems from the fact that bacteria undergo genetic changes and, thus, can pass down resistance to its progeny. One way these changes occur is through spontaneous mutation. Bacterial cells develop enzymes that inactivate antibiotics, and pump mechanisms that export antibiotics outside of the cell, to name a few. Another way resistance can propagate is through inappropriate antibiotic consumption. For example, since antibiotics are to be used against bacterial infections, a doctor prescribing an antibiotic for a patient with the common cold would be contributing to the development of resistant strains of bacteria.

The World Health Organization (WHO) and other healthcare organizations around the world are well aware of this problem and have voiced their concerns and strategies several times this year. In April, the WHO remarked, “a post-antibiotic era – in which common infections and minor injuries can kill – far from being an apocalyptic fantasy, is instead a very real possibility for the 21st Century.”⁶ In June, the British public voted to put forth a fund of £10 million towards “[tackling] growing levels of antimicrobial resistance.”⁷ In September, the White House released an executive order for combating antibiotic-resistant bacteria with hopes to “work domestically and internationally to prevent, detect, and control illness and death related to infections caused by antibiotic-resistant bacteria by implementing measures to mitigate the emergence and spread of antibiotic resistance and ensuring the continued availability of therapeutics for the treatment of bacterial infections.”⁸

This executive order is in line with the FDA’s 2013 provision, the Generating Antibiotics Incentives Now (GAIN) Act. Under this Act, certain antibiotics are reviewed in an expedited manner, “typically shaving four months off review times.”⁹ To have this priority, an antibiotic must be given Qualified Infectious Disease Product (QIDP) designation through its ability to target a select list of 21 life-threatening pathogens including Candida, Streptococcus, and Staphylococcus species.

Dalbavancin is the first drug to receive QIDP designation for treatment of Streptococcus and Staphylococcus species. Tedizolid phosphate and oritavancin were also given QIDP status prior to their approvals.

There is still a long way to go before the problem of microbial resistance is solved. Nonetheless, the federal government is providing the pharmaceutical industry flexibility during the new drug application process and these three recent drug approvals are products of the federal government’s efforts against growing resistance. As pharmacists and health professionals, we can also help by identifying signs of non-adherence in patients and counseling them about the importance of taking the antibiotic as prescribed, both in terms of regimen and duration of treatment. By monitoring and informing patients about the correct use of antibiotics, we can contribute the fight against antibiotic resistance, patient by patient.

 

SOURCES:

1. FDA. FDA approves dalvance to treat skin infections. FDA website. May 23, 2014. Available at http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm398724.htm. Accessed October 13, 2014.
2. FDA. FDA approves sivextro to treat skin infections. FDA website. June 20, 2014. Available at http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm402174.htm. Accessed October 13, 2014.
3. FDA. FDA approves orbactiv to treat skin infections. FDA website. August 6, 2014. Available at http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm408475.htm. Accessed October 13, 2014.
4. Nathan C, Cars O. Antibiotic resistance–problems, progress, and prospects. N Engl J Med. 2014;371(19):1761-3.
5. Davies J. Where have All the Antibiotics Gone?. Can J Infect Dis Med Microbiol. 2006;17(5):287-90.
6. WHO. Antimicrobial resistance: global report on surveillance 2014. WHO website. April 2014. Available at http://www.who.int/drugresistance/documents/surveillancereport/en/. Accessed October 13, 2014.
7. Antibiotics. Longitude Prize 2014. Available at http://www.longitudeprize.org/challenge/antibiotics. Accessed October 13, 2014.
8. The White House. National Strategy for Combating Antibiotic-Resistant Bacteria. Sept 2014. Available at http://www.whitehouse.gov/sites/default/files/docs/carb_national_strategy.pdf. Accessed October 13, 2014.
9. Woodcock J. Three encouraging steps towards new antibiotics. FDA Voice. September 23, 2014. http://blogs.fda.gov/fdavoice/index.php/2014/09/three-encouraging-steps-towards-new-antibiotics/. Accessed October 13, 2014.

[pubmed_related keyword1=”antibiotic” keyword2=”resistance” keyword3=”infection”]