Antiviral photodynamic therapy seems underfunded

By freedomandutility @ 2022-07-31T15:55 (+10)

Antiviral photodynamic therapy basically involves:

Here's a review on antiviral photodynamic therapy:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7883714/

It seems like photodynamic therapy is effective across a broad range of microbes and I can't think of obvious dual-use risks.

There also don't seem to be many human trials, so this seems like an underfunded area and could be useful for pandemic response.

I don't have time to write a more detailed post on this but would encourage anyone reading this to do so.

(I'm experimenting with making lower-effort posts, because restricting myself to higher quality posts was resulting in me making close to 0 posts. If you think this kind of post is too low-effort and makes the EA Forum worse overall, let me know in the comments).

weeatquince @ 2022-07-31T19:29 (+4)

Very useful. Will look at it. Thanks for the short post.

freedomandutility @ 2022-07-31T21:45 (+3)

Thanks!

Joe Torres @ 2022-08-01T16:28 (+2)

One of the main challenges of photodynamic therapy is that biological tissues absorb and scatter the light used in the therapy.[1]  This seems to limit the effectiveness of such therapies to tissue depths less than 1-2cm.

The review article cites three studies as examples of in vivo photodynamic therapy; however, none of these overcome the challenge of tissue penetration.  The first study [2] is a skin xenograft model (which needs very little tissue penetration and does not seem obviously superior to topical therapy), the second [3] pre-treats virus before inoculation (technically not an in vivo model of photodynamic therapy), and the third [4] was in oysters and used curcumin[5].

  1. ^

    https://en.wikipedia.org/wiki/Near-infrared_window_in_biological_tissue

  2. ^

    https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4459584/

  3. ^

    https://pubmed.ncbi.nlm.nih.gov/22153019/

  4. ^

    https://pubmed.ncbi.nlm.nih.gov/26117199/

  5. ^

    https://www.science.org/content/blog-post/curcumin-will-waste-your-time

freedomandutility @ 2022-08-01T17:29 (+2)

Thanks for adding this.

I’m still optimistic because it sounds plausible that a device / procedure can be developed to deliver the light to tissues from inside the airway.

Roddy MacSween @ 2022-07-31T21:04 (+2)

Why does this need charitable funding rather than existing profit incentives being sufficient? Is the assumption that non-pandemic use wouldn't be profitable enough?

freedomandutility @ 2022-07-31T21:43 (+4)

EA funding would just speed things up, which I think would be worth the money.

I haven’t read enough to work out why this hasn’t seem more investment yet - a potential reason is that it might be harder to protect intellectual property and profit off these treatments compared to a medication.