Dear David

 It's a broad generalisation to say there have been no new classes of antibiotics. There have been some but unfortunately not against many of the most deadly bacteria.

 Bacteria are generally divided into 3 classes, the mycobacteria (TB etc), and Gram-positives (MRSA etc) and Gram-negatives (E coli etc). There have been a few new classes of antibiotic in recent decades against 2 of the 3, though not against Gram-negatives such as E coli, K. pneumoniae, A baumannii and P aeruginosa. Gram-negatives have an extra cell coat (2 instead of just one that Gram-positives have) which makes it much more difficult for antibiotics to gain entry. And these bacteria have also developed capability to pump out our antibiotics or degrade them rapidly. Those four Gram-negatives in particular are a major cause for concern, as we have had no effective new chemical classes invented against them since the 1970s. They are increasingly gaining resistance to our best antibiotics. There have been some new antibiotics against them launched onto the market but these are minor variations on the same old chemical templates. These are easier to discover but also easier for the bacteria to resist. We desperately need new chemical templates. All efforts have failed for nearly 4 decades.

 Apart from the scientific problems, there are commercial problems too. The pharmaceutical industry cannot make money from antibiotics for several reasons.

First, they are very difficult to invent. I heard a talk by Sir Andrew Witty, CEO of GlaxoSmithKline in which he said it has proved to be the hardest area of drug discovery. Scientists from both GSK and AstraZeneca separately published major review articles summarising over a decade of research in each company trying to find new antibiotics, with no success in either company.

Second, the commercial model is broken. Antibiotics cost a lot to invent yet get used for only a few days when needed, compared with drugs for chronic indications such as cancer, high blood pressure and diabetes which are easier to invent and get used every day. So companies make little money from antibiotics.

 Third, if a drug company does in future invent a stunningly good antibiotic, there will be intense pressure to reserve it for use as a last resort when other antibiotics fail, to save it from resistance for for use in the most seriously ill patients. Again, this indicates low sales volume. It would need very high prices or a very different commercial model to overcome this problem. The review that David Cameron established under Jim O'Neill a few years ago proposed a new commercial model, and also John Rex at Astra Zeneca has been a thought leader on new models. I have attended several meetings with them both including meetings with politicians in parliament but progress seems to have stalled now we have a new government with other priorities.

Re amoxycillin, my view is that it should never be used alone. It has been an excellent antibiotic for over 3 decades, one of the best, but inevitably bacteria are becoming resistant to it. There is a version in which it is used alongside a resistance breaker called clavulanic acid, (co-amoxyclav is the commercial name, and here is the Wikipedia entry https://en.wikipedia.org/wiki/Amoxicillin/clavulanic_acid). This combination is still effective for many infections. I carry it myself when I travel in the Himalayas, as I will be doing in coming weeks.

Finally, I thought I would add some advice for subscribers if they get a serious infection.

See below - a PDF of Dr David Brown';s full email is posted following my brief comment.

 

David Fuller's view

Dear David,

On behalf of all subscribers, thank you so much for this import email, generously and thoughtfully provided. It contains potentially lifesaving information.

As a personal aside, when a young, very nice temporary doctor at our personal surgery offered me amoxicillin for my developing chest infection, I recognised the name and accepted it rather hopefully. The 5-day course did nothing for my condition but caused me to optimistically assume that I was getting better.  The next two weeks were a disturbing reality check.  I trust I will be less naïve next time.  

Here is a PDF of Dr David Brown’s entire email.