Frequency Therapeutics — Hearing Loss Regeneration

[FGG]

Let's assume FX-322 is commercialized, would they have to complete another clinical trial if they wanted to improve the drug (for instance make the drug reach the lower frequencies)?

They'd likely have to do a 505 (b) (2) which is much shorter (median time 13 months for the whole thing, some as short as 6 months).

 

[Lucifer]

I'm quite surprised no one from here has been accepted for the trials. I would have thought a few from here would have been accepted.

 

[FGG]

I'm quite surprised no one from here has been accepted for the trials. I would have thought a few from here would have been accepted.

I'm sure someone has but can't post about it. I do know no social media is part of their NDA.

 

[Rb86]

Let's assume FX-322 is commercialized, would they have to complete another clinical trial if they wanted to improve the drug (for instance make the drug reach the lower frequencies)?

If it involved a new mechanism, yes. If it involved different dosing that was previously tested, no.

 

[Lucifer]

I'm sure someone has but can't post about it. I do know no social media is part of their NDA.

How would the NDA work in terms of if it's family and friends? Would you have to lie to them?

 

[FGG]

How would the NDA work in terms of if it's family and friends? Would you have to lie to them?

Not sure but that would be hard to fully pull off. I was specifically told "should you be accepted into this trial, the NDA includes no social media posting about the trial or your results."

Obviously, I didn't get into the trial but the most likely people in the trial would be if someone used to post in the research section and then doesn't anymore. They couldn't confirm it either way, though.

 

[Pero1234]

Let's assume FX-322 is commercialized, would they have to complete another clinical trial if they wanted to improve the drug (for instance make the drug reach the lower frequencies)?

I suspect that reaching the lower frequencies depends more on improving the delivery method than improving the drug itself.

If FX-322 turns out to be as effective as everyone hopes, the next big thing is a (non-intrusive?) delivery method that can reach the inner part of the cochlea. Not easy!

 

[FGG]

I suspect that reaching the lower frequencies depends more on improving the delivery method than improving the drug itself.

If FX-322 turns out to be as effective as everyone hopes, the next big thing is a (non-intrusive?) delivery method that can reach the inner part of the cochlea. Not easy!

Yes, they need a better hydrogel. Other companies have drugs that can reach the entire cochlea. Frequency will get there, too.

 

[brokensoul]

So, FX-322 uses PCA to divide and transdifferentiate progenitor cells into hair cells.

There are however two different hair cells in our cochlea. Inner hair cells (IHC) and outer hair cells (OHC).

These two types of hair cells may seem similar on the surface, in reality they are different in terms of position in the cochlea, actual structure or form, connectivity, actual functionality and likely also in terms of molecular structure.

These hair cells differ more than just the positioning of the stereocilia on the cuticular plate. IHC stereocilia are linear and OHC sterocilia are W-shaped.

Inner hair cells (IHCs), the sensory cells of the cochlea, are responsible for signal transduction. Lying in a single row along the internal side of the tunnel of Corti, they are connected to type I spiral ganglion neurons (of which the axons represent about 95% of auditory nerve fibres). Inner hair cells code the frequency and intensity of acoustic stimuli into a neural signal, which is then transmitted to the brain via the auditory nerve. The physiological properties of the inner hair cells relies upon the relationship between stimulation and the secretion of the neurotransmitter at the level of the synapse with the endbulbs of the auditory nerve. They have about 10 synapse ribbons on average, but this depends on the actual position of the IHC in the cochlea.

Outer hair cells (OHCs) are disposed in three rows on the external side of the tunnel of Corti. OHCs are quite atypical sensory cells. They start transduction classically (as IHCs), being excited by K+ entrance into the tips of stereocilia. However, this excitation instead of initiating an auditory message, triggers a reverse transduction process, feeding energy back into the Corti's organ. This electro-mechano transduction (also called active mechanism), due to OHC electro-motile properties, enhances the cochlear sensitivity and frequency selectivity. The OHCs synaptic organization correspond to their electro-motile properties. Vesiculated endings of the medial efferent system regulate the OHC motile properties. The primary physiological property of the outer hair cells is electromotility: they respond to mechano-electrical transduction (similar to that of the inner hair cells) by a mechanism of opposing transduction (electro-mechanical). This is an active amplification mechanism which gives the cochlea remarkable frequency selectivity and sensitivity.

There is a lot more to be said to clarify that IHCs and OHCs have similarities, but in reality are very different.

So this begs the question, what does FX-322 actually do when it comes to the difference between IHCs and OHCs?

When they speak of regenerating "hair cells", what do they actually mean?

Do they refer to OHCs or do they mean both? I know they hinted at regeneration of IHCs as well in their latest presentation, but this raises a lot of questions to be honest.

When their pair of small molecules triggers the molecular pathways of a progenitor cell (Atoh1 notch inhibition and WNT activation) are they referring to OHCs specifically or both? Is it intended that FX-322 regenerates both IHC and OHC?

In the case they are referring to both, does that mean that the supporting cells in the IHC area and the supporting cells in the OHC area are triggered in the same way, both using the same pathways?

If true, does this imply that the supporting cells, depending on where they are localized actually know that they have to mature into an IHC, OHC respectively? That would mean the supporting cells are actually different, but contain the same pathways to activate transdifferentiation?

Or is there a possibility that we're going to generate a OHC hair cell where an IHC hair cell needs to be generated?

Did their mouse models actually teach them anything in regards to the generation of IHCs versus OHCs?

Anyone have any insight into this?

 

[FGG]

So, FX-322 uses PCA to divide and transdifferentiate progenitor cells into hair cells.

There are however two different hair cells in our cochlea. Inner hair cells (IHC) and outer hair cells (OHC).

These two types of hair cells may seem similar on the surface, in reality they are different in terms of position in the cochlea, actual structure or form, connectivity, actual functionality and likely also in terms of molecular structure.

These hair cells differ more than just the positioning of the stereocilia on the cuticular plate. IHC stereocilia are linear and OHC sterocilia are W-shaped.

Inner hair cells (IHCs), the sensory cells of the cochlea, are responsible for signal transduction. Lying in a single row along the internal side of the tunnel of Corti, they are connected to type I spiral ganglion neurons (of which the axons represent about 95% of auditory nerve fibres). Inner hair cells code the frequency and intensity of acoustic stimuli into a neural signal, which is then transmitted to the brain via the auditory nerve. The physiological properties of the inner hair cells relies upon the relationship between stimulation and the secretion of the neurotransmitter at the level of the synapse with the endbulbs of the auditory nerve. They have about 10 synapse ribbons on average, but this depends on the actual position of the IHC in the cochlea.

Outer hair cells (OHCs) are disposed in three rows on the external side of the tunnel of Corti. OHCs are quite atypical sensory cells. They start transduction classically (as IHCs), being excited by K+ entrance into the tips of stereocilia. However, this excitation instead of initiating an auditory message, triggers a reverse transduction process, feeding energy back into the Corti's organ. This electro-mechano transduction (also called active mechanism), due to OHC electro-motile properties, enhances the cochlear sensitivity and frequency selectivity. The OHCs synaptic organization correspond to their electro-motile properties. Vesiculated endings of the medial efferent system regulate the OHC motile properties. The primary physiological property of the outer hair cells is electromotility: they respond to mechano-electrical transduction (similar to that of the inner hair cells) by a mechanism of opposing transduction (electro-mechanical). This is an active amplification mechanism which gives the cochlea remarkable frequency selectivity and sensitivity.

There is a lot more to be said to clarify that IHCs and OHCs have similarities, but in reality are very different.

So this begs the question, what does FX-322 actually do when it comes to the difference between IHCs and OHCs?

When they speak of regenerating "hair cells", what do they actually mean?

Do they refer to OHCs or do they mean both? I know they hinted at regeneration of IHCs as well in their latest presentation, but this raises a lot of questions to be honest.

When their pair of small molecules triggers the molecular pathways of a progenitor cell (Atoh1 notch inhibition and WNT activation) are they referring to OHCs specifically or both? Is it intended that FX-322 regenerates both IHC and OHC?

In the case they are referring to both, does that mean that the supporting cells in the IHC area and the supporting cells in the OHC area are triggered in the same way, both using the same pathways?

If true, does this imply that the supporting cells, depending on where they are localized actually know that they have to mature into an IHC, OHC respectively? That would mean the supporting cells are actually different, but contain the same pathways to activate transdifferentiation?

Or is there a possibility that we're going to generate a OHC hair cell where an IHC hair cell needs to be generated?

Did their mouse models actually teach them anything in regards to the generation of IHCs versus OHCs?

Anyone have any insight into this?

Have you seen their publications page on their website? That's probably the best insight we have.

We also know that audiogram changes = OHC and from Q and A any cochlear synaptopathy changes after hair cell regeneration would have to be IHC. So, both.

As far as the "how", I would look to their publications page

 

[HootOwl]

Anyone have any insight into this?

Here's the full paper - https://www.cell.com/cell-reports/fulltext/S2211-1247(17)30136-5

It's a chunky boy so have fun. It'll tell you everything you could want to know about the process.

TL;DR: for the paper: Both IHC and OHC are where they should be. Both are regenerated in varying degrees. Both show the appropriate markers for their specific variety - i.e.: IHC look like IHC and OHC look like OHC.

 

[brokensoul]

Publications referenced on:

https://www.frequencytx.com/science/publications/

2017

McLean WJ, Yin X, Lu L, Lenz DR, McLean DT, Langer R, Karp JM, Edge ASB. Clonal Expansion of Lgr5-Positive Cells from Mammalian Cochlea and High-Purity Generation of Sensory Hair Cells. Cell Reports. 2017 Feb 21; Vol 18 Issue 8, p1917–1929.

https://www.cell.com/cell-reports/fulltext/S2211-1247(17)30136-5

2016

McLean WJ, McLean DT, Eatock RA, Edge AS. Distinct capacity for differentiation to inner ear cell types by progenitor cells of the cochlea and vestibular organs. Development. 2016 Oct 27. Online.

https://dev.biologists.org/content/143/23/4381.long

Yin X, Mead BE, Safaee H, Langer R, Karp JM, Levy O. Engineering Stem Cell Organoids. Cell Stem Cell. 2016 Jan 7; Vol 18 Issue 1, p25-38.

https://www.cell.com/cell-stem-cell/fulltext/S1934-5909(15)00550-0 2015

Tong Z, Solanki A, Hamilos A, Levy O, Wen K, Yin X, Karp JM. Application of biomaterials to advance induced pluripotent stem cell research and therapy. The Embo Journal. 2015 Apr 15; Vol 34 Issue 8, p987-1008.

https://www.embopress.org/doi/full/10.15252/embj.201490756

2014

Schuth O, McLean WJ, Eatock RA, Pyott S. Distribution of Na,K-ATPase α Subunits in Rat Vestibular Sensory Epithelia. Journal of the Association for Research in Otolaryngology. 2014 Oct; Vol 15 Issue 5, p739–754.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4164683/

Yin X, Farin HF, van Es JH, Clevers H, Langer R, Karp JM. Niche-independent high-purity cultures of Lgr5+ intestinal stem cells and their progeny. Nature Methods. 2014 Jan;11(1):106-12.

https://www.ncbi.nlm.nih.gov/m/pubmed/24292484/


After skimming through the publications, I could only find the following in regards to IHC and OHC generation:

So it seems that FX-322 should regenerate both IHC and OHC.

If anyone else wants to have a look at those publications to see where exactly they address OHC versus IHC generation and confirm they are both generated properly with all expected characteristics, please do.

Thanks.

 

[brokensoul]

Here's the full paper - https://www.cell.com/cell-reports/fulltext/S2211-1247(17)30136-5

It's a chunky boy so have fun. It'll tell you everything you could want to know about the process.

TL;DR: for the paper: Both IHC and OHC are where they should be. Both are regenerated in varying degrees. Both show the appropriate markers for their specific variety - i.e.: IHC look like IHC and OHC look like OHC.

Ok, so FX-322 has both IHC and OHC generation covered and they have all expected functionality(?)

Ok, that is great to hear.

I didn't see the exact quotes that confirm this. Will need to look again.

So that would mean that the Lgr5+ progenitor cells have the properties to know that they need to transdifferentiate into IHC or OHC, since FTX only uses one solution that covers both IHC and OHC, ánd uses the same pathways on the progenitors to initiate the transdifferentiation.

 

[brokensoul]

I've also looked into morphology of hair cells and stereocilia specifically and I cannot seem to find a clear answer on my question if hair cells with dysfunctional stereocilia can remain present in the epithelium (or in other words if apopthosis always happens when the stereocilia are "messed up").

I did find the following quote which seems to imply that hair cells can remain present with flaccid or sheared stereocilia:

"Damage to the hair cells can occur via ototoxic drugs or loud sounds. Results of damage can vary from flaccid or sheared stereocilia to a complete extrusion of the cell body from the sensory epithelium."

 

[FGG]

I've also looked into morphology of hair cells and stereocilia specifically and I cannot seem to find a clear answer on my question if hair cells with dysfunctional stereocilia can remain present in the epithelium (or in other words if apopthosis always happens when the stereocilia are "messed up").

I did find the following quote which seems to imply that hair cells can remain present with flaccid or sheared stereocilia:

"Damage to the hair cells can occur via ototoxic drugs or loud sounds. Results of damage can vary from flaccid or sheared stereocilia to a complete extrusion of the cell body from the sensory epithelium."

Damaged hair cells can remain but none of these therapies seem to make a distinction between damaged or fully destroyed hair cells in terms of regeneration.

It seems your worry is that somehow your hair cells won't be "damaged enough" for this to work on you. Since louder noise and more severe ototoxins result in greater audiogram changes, it seems that for your hypothesis to be true more severe to profound hearing loss would be more amenable to regeneration and the data doesn't support that.

You seem to want an exact study on regeneration on each configuration of stereocilia. Regeneration hasn't been around long enough for that study specifically but nothing in the data we have so far suggest this is a problem.

 

[FGG]

Also, @brokensoul if, for some reason, it turned out mild damage doesn't lend itself to as much repair, there are countless ototoxins that you could take to further damage your hair cells into the heavily damaged zone.

Seriously, though, I think Coronavirus killing enough participants to where Frequency has to restart their trial is a bigger concern and I don't think that's very probable at all.

Try to remain optimistic. There is a lot of amazing biotech working on this problem.

 

[brokensoul]

Damaged hair cells can remain but none of these therapies seem to make a distinction between damaged or fully destroyed hair cells in terms of regeneration.

It seems your worry is that somehow your hair cells won't be "damaged enough" for this to work on you. Since louder noise and more severe ototoxins result in greater audiogram changes, it seems that for your hypothesis to be true more severe to profound hearing loss would be more amenable to regeneration and the data doesn't support that.

You seem to want an exact study on regeneration on each configuration of stereocilia. Regeneration hasn't been around long enough for that study specifically but nothing in the data we have so far suggest this is a problem.

No, unfortunately my worries go way beyond the potential complications of hearing regeneration.

But within that spectrum I do wonder about that specific potential problem. It relates to tinnitus potentially not being resolved if dysfunctional hair cells/stereocilia remain present. A fair question I believe. If FX-322 addresses this as well, then it seems that regenerating all hair cells in the cochlea, achieving a near perfect state, should someday be feasible. That would be beyond amazing. This perfection is however not yet possible if damaged hair cells/stereocilia remain present and are not addressed by FX-322.

Just throwing the question out there. If it cannot be answered then that is perfectly fine by me.

Combining this with a working solution to repair and regenerate synapse ribbons on IHCs and OHCs, means that the outlook for those with basic cochlear damage seems to be very positive.

 

[brokensoul]

Also, @brokensoul if, for some reason, it turned out mild damage doesn't lend itself to as much repair, there are countless ototoxins that you could take to further damage your hair cells into the heavily damaged zone.

Seriously, though, I think Coronavirus killing enough participants to where Frequency has to restart their trial is a bigger concern and I don't think that's very probable at all.

Try to remain optimistic. There is a lot of amazing biotech working on this problem.

I've thought the same. We have plenty ototoxins, but would you really want to go down that route? Anyhow, we'll already see what phase 2a teaches us in regards to tinnitus.

Contrary to what you may think, I'm actually very positive for those who have cochlear damage. My questions are only to have insight into how well everything is covered by what we know today.

Unfortunately I know that it's not certain that I'm personally in that category, but I am honestly happy for those that will be helped with hearing regeneration. I really am very positive about hearing regeneration and I do think it will resolve tinnitus for a lot of people.

 

[FGG]

I've thought the same. We have plenty ototoxins, but would you really want to go down that route? Anyhow, we'll already see what phase 2a teaches us in regards to tinnitus.

Contrary to what you may think, I'm actually very positive for those who have cochlear damage. My questions are only to have insight into how well everything is covered by what we know today.

Unfortunately I know that it's not certain that I'm personally in that category, but I am honestly happy for those that will be helped with hearing regeneration. I really am very positive about hearing regeneration and I do think it will resolve tinnitus for a lot of people.

I'm in the same boat. I know I have some cochlear damage but Azithromycin is also toxin to the auditory portion of the brainstem. For everyone with noise induced hearing loss especially, I know they will be fine.

As excited as I am about cochlear regeneration, I'm still worried, I will never hear a song again the rest of my life and that devastates me.

 

[brokensoul]

I'm in the same boat. I know I have some cochlear damage but Azithromycin is also toxin to the auditory portion of the brainstem. For everyone with noise induced hearing loss especially, I know they will be fine.

As excited as I am about cochlear regeneration, I'm still worried, I will never hear a song again the rest of my life and that devastates me.

The medical field does not take the potential damage of medications serious enough.

Some medications are ototoxic, but are not classified as such. Even when there is data supporting ototoxic mechanisms, they still deny it or hide behind 'very low occurrence' and obviously pharmaceutical companies are not going to bother profoundly studying it or revealing that it can be damaging. Ototoxic damage is cumulative and I believe it's not or cannot be properly tested, unless it is very ototoxic and cannot be denied due to instantly noticeable damage.

What is even worse is that I believe there are several medications that in reality need to be reclassified as neurotoxic.

 

[Lucifer]

If they wanted to improve the drug delivery method efficiently would they need to use a different type of gel that reaches all frequencies?

 

[john paul]

If there has been more improvements with the word scores and if tinnitus reduces in Phase 2a by increasing dosage it would be a shame if it was Phase 2b next.

It wouldn't matter to me. If they came and said this company has improved someone's tinnitus and hearing at some point during this year I could get through a few more years knowing help was coming. It would be such a relief to hear them say we cured someone's tinnitus and fixed their broken ears with pure simple effective science.

It would be such a relief. It's the only thing that gets me through each day without worrying too much or thinking too much into the future. I really just hope they can tell us some super positive news but I really feel like if anyone is going to do it, it's going to be Frequency Therapeutics. It wouldn't come as a shock to me if they said we cracked it, we can more than likely help millions of people.

 

[Lucifer]

It wouldn't matter to me. If they came and said this company has improved someone's tinnitus and hearing at some point during this year I could get through a few more years knowing help was coming. It would be such a relief to hear them say we cured someone's tinnitus and fixed their broken ears with pure simple effective science.

It would be such a relief. It's the only thing that gets me through each day without worrying too much or thinking too much into the future. I really just hope they can tell us some super positive news but I really feel like if anyone is going to do it, it's going to be Frequency Therapeutics. It wouldn't come as a shock to me if they said we cracked it, we can more than likely help millions of people.

But it will be nice if they can go directly to Phase 3 after the Phase 2a is done. I reckon they should have tested for hyperacusis in Phase 2a but hopefully they test for it in Phase 3.

There are a lot of people suffering at the moment due to tinnitus and hyperacusis and the faster these treatments come out the better. I do not want to have to worry about the future every day.

 

[Lucifer]

Does it state anywhere that once they have injected FX--322 into your ear, you have to stay in that position for an hour?

Audion Therapeutics/Regain states that the patient must stay in that position for an hour.

 

[brokensoul]

Does it state anywhere that once they have injected FX--322 into your ear, you have to stay in that position for an hour?

Audion Therapeutics/Regain states that the patient must stay in that position for an hour.

They didn't state it, but I believe it is part of transtympanic injections, otherwise the fluid will leak into the eustachian tube.

I also believe that @JohnAdams said that he wasn't allowed to swallow during that period.

There are probably several people here who already had such procedure and can shed some light on this.

 

[FGG]

They didn't state it, but I believe it is part of transtympanic injections, otherwise the fluid will leak into the eustachian tube.

I also believe that @JohnAdams said that he wasn't allowed to swallow during that period.

There are probably several people here who already had such procedure and can shed some light on this.

This makes me wonder if any variation existed in phase 1 results due to patients not following the "no swallowing" for X amount of time rule as thoroughly as others.

 

[brokensoul]

This makes me wonder if any variation existed in phase 1 results due to patients not following the "no swallowing" for X amount of time rule as thoroughly as others.

Quite possibly. It's real hard to not swallow for 45 minutes up to one hour. You need to suppress the reflex and let it all drool out.

 

[lymebite]

There are probably several people here who already had such procedure and can shed some light on this.

An ENT gave me an intra-tympanic injection a few years ago (through the ear drum, similar to how FX-322 is administered). They projected the procedure on a big TV screen so I could watch the needle go into the ear drum.

The substance in the injection I received was a steroid. I had to keep my head sideways and still for about 10 minutes after the injection so that the steroid did not wash down the eustachian tube.

 

[brokensoul]

They projected the procedure on a big TV screen so I could watch the needle go into the ear drum.

"I am now going to push a big ass needle in your ear. Please watch the screen to follow the procedure. Stay calm and don't move!"

 

[Lucifer]

Quite possibly. It's real hard to not swallow for 45 minutes up to one hour. You need to suppress the reflex and let it all drool out.

I think I will struggle with this if I couldn't swallow for 45 minutes to 1 hour.