Hacker News Reader

Comment by Orangeair | Hacker News Reader

Is there any particular reason we can't just create new antibiotics? Is there something inherent in the current design of antibiotics that prevents creating new versions of what we have? If so, is there an 'upper limit' of how many we can create, and have we reached it already?

View on HN

Most antibiotics are not created but discovered. They are often species of fungus or other microorganisms that happen to attack certain kinds of bacteria. Take any place on earth where you might find microorganisms, grow them in a culture and then test their effects until you find one with the desired properties (kills bacteria but not human cells) and then you might be able to develop a new drug from it. The problem is we're running out of places to scoop up microorganisms from and the newest drugs are being made from fungi found deep in the most inaccessible caves underground for which bacteria above ground has not developed a resistance to. It's an evolutionary arms race which we're ultimately destined to lose which is why we need to find better ways of killing bacteria.

Couldn't evolution be accelerated in the lab? If the bacteria can evolve a way to thwart a fungus' defense, wouldn't it stand to reason that the fungi could evolve a new defense as well?

The reason is that creating antibiotics is not profitable enough, and so 15 years ago pharmas stopped most research on them.

Not sure why this was down voted because it's true. Only a few big pharma have R&D programs in the antibacterial space. As a reply above states, the current system penalizes new antibiotics by reserving them for only the most severe cases. With the cost of a new antibiotic approval in the hundreds of millions of dollars, companies put their R&D dollars into areas with better returns.

That being said, a few new legislative changes have happened and will happens (GAIN Act approved, DISARM Act being considered) that will change the economics of antibiotic research and have already prompted drug companies to get back into the field.

It's an active research topic, and little progress has been made recently.

You'd have to find a new class of drugs that is safe for humans at the toxic dose for bacteria.

If this[1] research leads anywhere, we may not need totally new drugs. Only modify the existing with polymers.

[1]http://www.sciencedaily.com/releases/2014/04/140414154454.ht...

I'd go a step further - at some point, there will be NO possible new antibiotics to develop or design. At the core, the concept of antibiotics depends on bacteria having a sufficiently different metabolism than our own cells, so that some compound disrupts internal processes of bacteria without affecting the similar process of 'good' cells. We have found a couple such metabolic pathways, and have various drugs targeting them. The problem is that once bacteria become drug-resistant, i.e., mutate so that they use a bit different chemistry, most likely more similar to our cells (obtained from our own DNA?) - then you can't do that anymore.

Perhaps there are some new antibiotics to be found, perhaps there aren't; but in any case there's an end of the road somewhere. After that, only radically different mechanisms would work - vaccines, phages, nanobots, something else, but not antibiotics.

There are plenty of bacterial targets that we haven't even started to explore. Many of the current antibacterials work by interrupting cell wall synthesis. There are many different protein involved in cell wall synthesis. Stop anyone of those from working and you have a new antibiotic mechanism.

We are creating new versions of what we have already. When you hear something referred to, for example, as a "beta-lactam antibiotic", what that actually means is a more creative version of penicillin. We tack new functional groups onto antibiotics to try to outpace resistance mechanisms, but its a stalling tactic, not a solution.

New antibiotic classes are hard to find. You need to find compounds that are lethal to bacterial cells (but not our cells) that there's no pre-existing immunity to. That's an extremely tall order, and we've run out of easy sources for those compounds.

IANA*, but as I understand it there are fundamentally two forms of antibiotic - variations on penicillin, and variations on vancomycin. While varying the exact form of antibiotic works to a point, eventually you run into the problem that bugs become resistant to the basic underlying common mechanism within the family of antibiotics. Everyone accepts this process with penicillin-ish drugs, but when it starts happening to the vancomycin-ish drugs, that's when it gets scary, because there is no 3rd tier.

There are a couple dozen classes of antibiotics, of which penicillins and glycopeptides (vancomycin) are just two. Personally, I have just been through 4 classes while trying to fight cellulitis (a penicillin, 2 lincosamides, a sulfonamide, and a tetracycline). I was probably a day or two away from being hospitalized for IV glycopeptide treatment. In my case, the problem was the speed with which the infection was progressing; I had daily appointments with my orthopedist until we found the right combination. Still, there are a variety of antibiotics that can be tried, alone or in combination. There is only a fuzzy concept of "tiers". Its more about strength and side effects.

Apparently not. This article (http://www.telegraph.co.uk/finance/newsbysector/pharmaceutic...) suggests its a case of economics. That is new antibiotics would be kept back as a last line of defence only; therefore not as profitable.

If we were a rational species, we would recognize we're at war with another species that's killing millions of us, and spend a portion of our military budget on antibiotics research, instead of leaving it all up to the private sector.

We spend tax money on defense because it's a public good and in the absence of tax dollars there's no money in it. The same applies here.

It isn't what you mean, but DARPA does fund medical research, including treatments for infection. And USAMRIID ends up doing some research into treatments.

Reply on news.ycombinator.com