Division of Dockets Management (HFA 305) Food and Drug Administration 5630 Fishers Lane Room 1061 Rockville, MD 20852

Transcription

1 December 18, 2012 Division of Dockets Management (HFA 305) Food and Drug Administration 5630 Fishers Lane Room 1061 Rockville, MD Re: Comments on Docket No. FDA 2012 N 1037; Establishing a List of Qualifying Pathogens That Have the Potential to Pose a Serious Threat to Public Health Dear Sir/Madam: The Infectious Diseases Society of America (IDSA) is pleased to submit comments for the above referenced Food and Drug Administration (FDA) public hearing on establishing a list of qualifying pathogens that have the potential to pose a serious threat to public health. IDSA represents nearly 10,000 infectious diseases physicians and scientists devoted to patient care, prevention, public health, education, and research in the area of infectious diseases. Our members care for patients of all ages with serious infections, including meningitis, pneumonia, tuberculosis, HIV/AIDS, antibiotic-resistant bacterial infections such as those caused by methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE) and Gram-negative bacterial infections such as Acinetobacter baumannii, Klebsiella pneumoniae, and Pseudomonas aeruginosa, and emerging infections such as the 2009 H1N1 influenza virus. IDSA recognizes the importance of targeting incentives to the areas of greatest unmet medical need. With this goal in mind, IDSA is pleased to address the specific questions posed by FDA. 1. The Food and Drug Administration Safety and Innovation Act (FDASIA) requires FDA to consider the following factors in establishing and maintaining the list of qualifying pathogens: The impact on the public health due to drug-resistant organisms in humans; The rate of growth of drug-resistant organisms in humans; The increase in resistance rates in humans; and The morbidity and mortality in humans. How should these factors be applied to a pathogen to determine whether it should be included in the list?

2 PAGE TWO IDSA Comments on Establishing a List of Qualifying Pathogens In determining a pathogen s impact on the public health, FDA should consider the current incidence of infection with resistant strains of this pathogen. Further, FDA should consider the prevalence of colonization with this pathogen to the extent that colonization is a predisposing factor for infection of the colonized individual or others. The impact on public health should also consider ease of transmission. Another factor in a resistant pathogen s potential to impact public health is the availability of effective, evidence-based prevention measures that reduce the risk of spread of the resistant pathogen. Resistant pathogens for which proven and easily deployable interventions to prevent spread exist (e.g., immunization), would likely pose less of a threat than those for which interventions to prevent spread are less effective or difficult to deploy (e.g., universal screening, contact precautions and cohorting of colonized patients). In analyzing these factors, FDA should consider practical experience in the clinical care and public health systems as well as whether sufficient operational capacity exists to successfully implement preventive interventions. The rate of increase of growth of drug-resistant organisms in humans and the increase in resistance rates in humans are critical factors as well. To the extent possible, FDA should consider a ten-year projected incidence of infection (or prevalence of colonization) with individual pathogens based on their current trajectory of spread, or potential trajectory of spread based on experience with other similar resistant pathogens. FDA also should consider the potential ease with which genetic determinants conferring resistance transfer to pathogens from other organisms. To determine whether a resistant pathogen poses an excess burden of morbidity and mortality, FDA should consider various measures, including hospital length of stay, courses of antimicrobial therapy, need for additional medical interventions or rehabilitative therapies, temporary or permanent disability, and days lost from work or school. 2. Aside from the considerations noted in question 1 (i.e., those required by section 505(E)(f)(2)(B)(i) of the FD&C Act), are there any other factors FDA should consider when establishing and maintaining the list of qualifying pathogens? If so, how should these factors be applied to a pathogen to determine whether it should be included in the list? IDSA encourages FDA to consider the availability of safe and effective therapeutic options to treat infections caused by resistant pathogens. Pathogens for which there are no or very limited treatments or for which the only available, effective treatments present significant toxicities should receive high priority. In addition, pathogens that have demonstrated the capacity to quickly develop resistance to alternative therapy should be high priorities. FDA should consider the financial impact of the emergence and spread of resistant pathogens. Costs should be measured from the societal perspective, including direct and indirect costs of infection (including health care costs and lost productivity), as well as activities that may need to be undertaken to prevent spread of infection.

3 PAGE THREE IDSA Comments on Establishing a List of Qualifying Pathogens FDA also should consider the extent to which a pathogen is resistant and the impact of resistance on clinical care. The greatest medical need is for agents to treat pathogens that are extensively drug-resistant (XDR) and pan-drug-resistant (PDR). 3. Which specific pathogens do you believe should be listed as qualifying pathogens? Provide justification for your recommendations, including how you applied the considerations described in section 505E(f)(2)(B)(i) of the FD&C Act, and any other factors that you considered, in recommending the pathogen for inclusion on the list of qualifying pathogens. ESKAPE Pathogens: The ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumanii, Pseudomonas aeruginosa, Escherichia coli and Enterobacter species) cause serious and life-threatening infections, are extremely difficult and in many cases impossible to effectively treat, and clearly meet the required criteria for qualifying pathogens. 1 ESKAPE pathogens currently cause the majority of U.S. hospital infections and effectively escape the effects of available drugs. 2 More people now die of MRSA infection in U.S. hospitals than of HIV/AIDS and tuberculosis combined. 3 While some intravenous treatment options for MRSA exist, oral agents are desperately needed. XDR Klebsiella or XDR Acinetobacter bacteria kill up to 50% of infected patients despite treatment with last resort drugs, and resistance rates for these pathogens continue to climb. Therapeutic options for ESKAPE pathogens are extremely limited such that clinicians are often forced to use obsolete drugs, such as colistin, that are associated with significant toxicity and for which there is a lack of robust data to guide dosage regimen or duration of therapy. 4 For example, all strains of Klebsiella and E. coli containing the New Delhi metallo-beta-lactamase (NDM-1) (see more below) enzyme are resistant to all antibiotics except colistin and tigecycline, and 10% of these strains are even resistant to these drugs, making them truly pan resistant. 5 XDR Acinetobacter strains that are resistant to colistin are now being reported. Clostridium Difficile: C. difficile causes diarrhea linked to 14,000 American deaths each year. The incidence, deaths, and excess health-care costs resulting from C. difficile in hospitalized patients are at historic highs. From 2000 to 2009, the number of hospitalized patients with C. difficile infection (CDI) discharge diagnoses more than doubled, and the number with a primary CDI diagnosis more than tripled. Deaths related to C. difficile increased 400% between 2000 and Much of the recent increase in the incidence and mortality of CDIs is attributed to the 1 Combating Antimicrobial Resistance: Policy Recommendations to Save Lives, Clin Inf Dis; 2011; Boucher, Helen; Talbot, George; Bradley, John; Edwards Jr., John; Gilbert, David; Rice, Louis; Scheld, Michael; Spellberg, Brad; Bartlett, John. Bad Bugs, No Drugs: No ESKAPE! An Update from the Infectious Diseases Society of America, Clin Inf Dis 2009; 48: Klevens RM, Edwards JR, Tenover FC, McDonald LC, Horan T, Gaynes R. Changes in the epidemiology of methicillin-resistant Staphylococcus aureus in intensive care units in US hospitals, Clin Inf Dis 2006; 42: Falagas ME, Kasiakou SK. Colistin: the revival of polymyxins for the management of multidrug-resistant gramnegative bacterial infections. Clin Inf Dis 2005; 40: Kumarasamy 10 Lancet Infectious Diseases 10:

4 PAGE FOUR IDSA Comments on Establishing a List of Qualifying Pathogens emergence and spread of a hypervirulent, resistant strain of C. difficile. CDI is a serious threat not only in hospitals, but across the health care continuum. In fact, about 75% of CDIs first show symptoms in nursing home patients or in people recently cared for in doctors offices and clinics. Because C. difficile can live for long periods on surfaces it is easily transmitted from patient to patient. 6 Multidrug-Resistant Tuberculosis (MDR TB) and Extensively Drug-Resistant Tuberculosis (XDR TB): MDR TB is resistant to at least isoniazid and rifampin, the two most potent TB drugs. XDR-TB is resistant to isoniazid and rifampin, plus any fluoroquinolone and at least one of three injectable second-line drugs (i.e., amikacin, kanamycin, or capreomycin). Patients with these forms of TB must be treated with less effective and more toxic regimens. Infection with highly resistant strains of M. tuberculosis are of special concern for people with Human Immunodeficiency Virus (HIV) infection or other conditions that can weaken the immune system. They are more likely to develop TB disease, and also have a higher risk of death. Curing resistant TB can cost 200 times as much as curing typical TB; it also can take years, and some of the drugs cause side effects like deafness and psychosis. Resistant TB is a growing problem. A study published in The Lancet in October 2012 concerning more than 1,200 TB patients in 7 countries found that 44 percent of the TB strains identified showed resistance to at least one second-line drug. Although many of the most serious resistant TB cases occur in foreign countries, our increasingly global economy and high levels of international travel make this a threat the U.S. cannot ignore. Neisseria gonorrhoeae: Neisseria gonorrhoeae has demonstrated the ability to develop resistance to almost every antibiotic recommended for treatment: sulfonamides, tetracycline, penicillin, and, most recently, fluoroquinolones. CDC s surveillance is now showing disturbing trends of decreasing susceptibility to cephalosporins the last line of defense for treating gonorrhea. Actual treatment failures have been reported in other parts of the world, raising concerns that strains of gonorrhea with decreased susceptibility will be imported into the U.S. by travelers. Multi-drug resistant gonorrhea would have substantial health and economic consequences. First, there would be an increase in gonorrhea rates in the population, because people with gonorrhea will remain infectious for a longer period of time. Modeling studies suggests that gonorrhea prevalence in the population could increase by 7% to 40% per year as a result of antimicrobial resistance developing in a population without additional therapies. This would lead to increases in pelvic inflammatory disease in women (estimated cost, $585 million) and epididymitis in men (estimated cost, $15 million). Second, because gonorrhea can facilitate the acquisition and transmission of HIV, the increase in gonorrhea prevalence could lead to increases in new HIV infections as well (estimated cost, $180 million). 7 6 Vital Signs: Preventing Clostridium difficile Infections, Morbidity and Mortality Weekly Report (MMWR); Centers for Disease Control and Prevention (CDC); March 9, 2012 / 61(09); Potential Emergence of Multi-Drug Resistant Gonorrhea, Fact sheet from the Centers for Disease Control and Prevention (CDC), Dec

5 PAGE FIVE IDSA Comments on Establishing a List of Qualifying Pathogens Emerging Infections: FDASIA provides mechanisms for FDA to periodically review the list of qualifying pathogens and make updates as new threats emerge. IDSA urges FDA to monitor the following emerging pathogens that may become serious threats in the coming years. Non-ESKAPE pathogens containing the NDM-1 enzyme Enteric pathogens developing greater resistance, including Salmonella and Shigella including fluoroquinolone-resistant strains and ESBL, carbapenemase, or NDM-1 containing strains Carbapenem-resistant Enterobacteriaceae (CRE) Resistant pathogens emerging in other countries that demonstrate the potential for a serious public health impact given the globalization of our society and the ease for infection to spread through international travel Fungal infections: Candida species are the third or fourth most common cause of nosocomial bloodstream infections in the U.S. In aggregate, candidemia is associated with an overall mortality in excess of 40%. In the last decade, there has been a progressive rise in azole resistance among Candida species. As an example, rates of resistance to fluconazole and voriconazole for C. glabrata exceed 20-30% in many centers; fluconazole resistance among C. albicans exceeds 10% in several larger medical centers. Echinocandins, generally thought to be active against most Candida species, have emerged as drugs of first choice for most patients with invasive candidiasis. Unfortunately, antifungal resistance is emerging to this class of antifungals and resistance rates exceeding 5% are reported at some centers. An even more ominous development relates to associated mortality and antifungal resistance among pathogenic molds. Patients with invasive aspergillosis and mucormycosis have associated mortality as high as 70%. In addition, broad spectrum azole resistance among Aspergillus species has recently been described in the Netherlands and has emerged as a major concern among many European experts. Recent surveys among cancer patients in the United Kingdom and parts of Western Europe suggest that as many as 28% of clinically relevant Aspergillus isolates are azole resistant. While this has yet to be recognized as a major phenomenon in the U.S., it is only a matter of time before multi-azole resistance becomes a major problem for immune-compromised patients in the U.S. due to the highly global nature of our society. IDSA hopes that these comments are useful to FDA as the agency moves forward to develop the list of qualifying pathogens. Should you have any questions, please contact Amanda Jezek, IDSA s Director of Government Relations at ajezek@idsociety.org or Sincerely, David A. Relman, MD FIDSA President