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Science Policy Around the Web – February 16, 2018

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By: Mohor Sengupta, PhD

Health Bacteria Cell Infection Microbiology Black

source: Max Pixel

Antibiotic discovery

A potentially powerful new antibiotic is discovered in dirt

Antibiotics have been in an ongoing, constant battle with the pathogens they are aimed to eliminate. Bacteria constantly mutate their genetic material to acquire resistance to anti-microbial drugs, making multi-drug resistance a global concern. Misuse or overuse of antibiotics contributes to this phenomenon. To address the issue of multi-drug resistance, a team of microbiologists at the Rockefeller University, NY, have conducted a large screen of natural products produced by soil-dwelling bacteria. According to Dr. Sean Brady, who heads the group, only a small fraction of the bacterial biodiversity is cultured in the lab and only a tiny fraction of chemicals produced by these bacteria are detectable. Identification of naturally produced chemicals by bacteria that have never been cultured in the lab provides a promising new direction towards anti-microbial therapies.

Dr. Brady’s group adopted a “culture-independent”, metagenomics approach to analyze chemicals secreted by unknown bacteria from soil samples. Their aim has not been to identify the bacteria in the samples but to look for DNA signatures associated with calcium dependent antibiotic properties. This means that the chemical they are looking for will act against bacteria only in the presence of calcium. After the identification of a gene potentially encoding a calcium dependent antibiotic, the researchers cloned it and made a laboratory grown bacteria (S. albus J1074) express it. The gene product is a new class of antibiotics that have been named “malacindin”. Dr. Brady’s research has shown that malacidins act by interfering with bacterial cell wall formation and have shown this antibiotic to be effective against a range of superbugs, including methicillin-resistant Staphylococcus aureus (MRSA). Calcium dependent antibiotics are believed to make it more difficult for the target bacteria to evolve resistance. Dr. Brady’s research was published in Nature Microbiology on February 12.

Conventional methods to isolate new antibiotics from laboratory cultured bacteria often lead to the same antibiotics being found over and over again, resulting in abandonment of such approaches in recent times. The novelty of Dr. Brady’s work lies in the use of natural sources, like soil, sewage, water etc. to isolate the genetic blueprint encoding anti-microbial chemicals, made easier with the use of metagenomics and large-scale sequencing. Researchers elsewhere are also using this approach to identify new antibiotics from natural sources. In the modern scenario of increasing deaths due to multi-drug resistance, this type of research is critical to rapid discoveries of novel antimicrobial therapies. Of course, getting the newly discovered drug into the market will not be fast, as Dr. Brady warns, yet this is an ingenious solution to discovering clinically useful antibiotics.

(Sarah Kaplan, The Washington Post)

Risk assessment

He Took a Drug to Prevent AIDS. Then He Couldn’t Get Disability Insurance

Pre-exposure prophylaxis (PrEP) is a practice of taking a drug to prevent HIV infection in persons with high risk of contracting it. In the year 2012, the F.D.A. approved Truvada, a drug originally approved for HIV treatment a decade earlier, for prevention of HIV infection (PrEP). Since then PrEP has become increasingly popular and as of 2017, an estimated 136,000 people in the United States were on PrEP. Several studies have shown that Truvada is highly effective in preventing HIV infection. However in the initial days of Truvada use,  some thought that individuals taking prophylaxis might overestimate its level of protection, leading them to engage in risky behavior they otherwise would have avoided. This belief is prevalent even today, as several insurance companies across the United States regularly deny disability and life insurance to men on PrEP on the basis that this treatment is indicative of an increased level of personal risk.

The repercussions of this policy, was exemplified when Dr. Philip J. Cheng of Brigham and Women’s Hospital at Harvard accidentally cut himself while preparing an HIV positive patient for surgery. The responsible behavior in this situation is to immediately take steps to prevent infection. Dr. Cheng did just that, by enrolling into PrEP. However, when he applied for a disability insurance, he was denied coverage because he was taking Truvada. He could not get the insurance company to cover him even after agreeing to sign a waiver of benefits in case he got infected.

Disability insurance is usually applied for by people whose livelihood depends on their income. For people like Dr. Cheng this insurance will guarantee him his lifetime of income in the case of a disability. Use of Truvada has not shown any adverse side-effects till date. In fact, it is said to be safer than aspirin, whose long term usage causes gastro-intestinal bleeding. It is a consensus among AIDS doctors across the USA that PrEP is necessary for individuals at high risk of contracting HIV. Denial of insurance to PrEP users by insurance companies has been likened to denying insurance for using car seat-belts by Dr. Robert M Grant, whose group led the clinical trial that established the importance of PrEP. Even more perplexing is the fact that life insurance companies are regularly providing insurance to people with other conditions that are managed by regular medications, like diabetes and heart diseases. Even former alcoholics who are now un-addicted are not denied.

Mr. Bennet Klein, a lawyer with Boston based GLAD, an organization of legal advocates and defenders of GLBTQ community has asked several insurance companies the reason for denying insurance to men on PrEP. In most interviews with various insurance companies he and others have heard a range of answers, some ambiguous. The general understanding is that insurance companies are increasingly following this trend because they suspect potential high-risk behavior in PrEP users. The crux here is that regardless of risky sexual behavior, PrEP is highly protective. A prominent work of research published in The New England Journal of Medicine in 2010 showed that tenofovir, one of the chief components of Truvada reduced the risk of HIV infection by 95 percent. The famous HPTN 052 clinical trial of 2011 also showed the efficacy of PrEP.

Because of the prevalence of insurance denials, several people, like Dr. Cheng have stopped using PrEP. It is critical that this trend is reversed, in the light of clear benefits of taking PrEP. While there are insurance companies that do provide disability and life insurance to PrEP users, cases like Dr. Cheng’s result in disappointment and eventual withdrawal from using PrEP.

(Donald G. McNeal Jr, The New York Times)

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Written by sciencepolicyforall

February 16, 2018 at 4:58 pm

Science Policy Around the Web – April 24, 2015

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By: Danielle Friend, PhD

photo credit: DSC03602.JPG via photopin (license)

Genetic-based Drug Discovery

23andMe will invent drugs using customer data

As of March 2015, 23andMe will no longer simply be known for direct-to-consumer genetic tests. 23andMe has now made progress toward their long-term goal of influencing drug discovery. 23andMe claims to have collected DNA from approximately 850,000 consumers through marketing of their $99 kit, and the company plans to use this genetic information to identify new drug targets. Additionally, 23andMe reports that approximately 80% of the consumers that purchase the kits have agreed to allow 23andMe to use their genetic information for this research. To help lead these discovery efforts, 23andMe recently hired Richard Scheller, who formerly lead research and development at Genetech, as the chief scientific director and head of operations. In addition to these in-house efforts, 23andMe has also recently formed partnerships with pharmaceutical companies, including both Pfizer and Genetech who plan to use the genetic information to develop drugs for diseases like Parkinson’s disease. Although the partnerships with companies like Pfizer and Genetech are clearly defined to help identify drug targets for particular diseases, 23andMe plans to organize their in-house research as a broad sweep through their databases without a particular disease in mind. However, 23andMe has mentioned that they have a particular interest in metabolic and immune system disorders, eye disease, and cancer. (Mathew Harper, Forbes; Ron Winslow, Wall Street Journal)

Transparency in Clinical Trial Data

World Health Organization calls for increased transparency in clinical trials

In mid-April, the World Health Organization (WHO) released a statement recommending that findings from all clinical trials be made public regardless of the results of the study. Dr. Marie-Paule Kieny, the assistant director-general for health systems and innovation with the WHO, stated that the goals of this new mandate are to “…promote the sharing of scientific knowledge in order to advance public health.” Additionally, Dr. Kieny also stated that, “failure to publicly disclose trial results engenders misinformation, leading to skewed priorities for both [research and development] and public health interventions,” and that “it creates indirect costs for public and private entities, including patients themselves, who pay for sub-optimal or harmful treatments.” Several factors may come between completed research and the publication of results. However, unpublished results (even if negative) can lead to the perception that treatments are more or less effective than they are. The WHO mandate requires that results from clinical studies be submitted to peer-reviewed journals within 1 year after the completion of data collection, and that the work should be published within 24 months in an open access journal. The WHO also asks that “key outcomes” — limited details of the study including the number of participants, main findings, and adverse events — be made available online within a year of study completion. Although these new requirements are a step in the right direction for clinical trial transparency, it remains unclear just how the WHO plans to enforce these recommendations. (Chris Whoolston, Nature Research Highlights; Martin Enserink, Science Insider; The World Health Organization)

Ebola Clinical Trials

Lack of patients hampers Ebola drug and vaccine testing

As attention on the Ebola outbreak in Africa has increased, more resources and medical assistance have been provided. Although the number of Ebola cases has significantly decreased due to these interventions, an unexpected troubling scenario has developed: Ebola vaccine clinical trials are now having trouble testing the efficacy of their vaccines due to the lack patient populations. In fact, one company has altogether halted their trial. Chimerix, a company running a trial for their antiviral drug, brincidofovir, has decided to end the trial altogether due to a lack of patients. In fact, the World Health Organization’s weekly report from April 19 states that new cases of Ebola are now down to a total of 33. Because of the dramatic decrease in Ebola cases, the public health community faces ethical issues regarding whether more promising drugs should be prioritized and given preferential access to patients and geographical regions. (Andrew Pollack, The New York Times; Richard Harris, National Public Radio; The World Health Organization; Kai Kupferschmidt, Science)

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Written by sciencepolicyforall

April 24, 2015 at 9:00 am