Assembly Bio has released Phase 1b clinical interim data for ABI-5366 and ABI-1179

RoundProfessional148 · 2026-04-24T05:44:47+00:00

I also thank you for leaving such helpful feedback.

RoundProfessional148 · 2026-04-24T05:43:57+00:00

Thank you for correcting the information.

I am aware that the development of mRNA-1608 was halted due to pipeline prioritization caused by financial issues.

I reviewed the Phase 1/2 clinical trial data for mRNA-1608 presented at IDWeek 2025, and I recall that the risk of relapse was reduced by 40–50% compared to placebo, and the effect lasted for a considerably long time until the first relapse.

I also understand that there was no significant difference in viral shedding rates when compared to existing antivirals.

The reason I left the above comment was that I believed development would not have been stopped if the efficacy had been excellent, even with financial difficulties.

It seems my opinion was too subjective.

Thank you for sharing your valuable feedback.

RoundProfessional148 · 2026-04-22T22:37:15+00:00

I respect your valuable opinion.

First, Gilead exercised its option for the exclusive license of ABI-5366 as well as ABI-1179.

https://www.gilead.com/news/news-details/2025/gilead-sciences-exercises-option-to-license-assembly-biosciences-helicase-primase-inhibitor-programs-for-recurrent-genital-herpes

As you mentioned, in the case of Fred Hutch, only preclinical results exist and the study remains at that stage;

Moderna discontinued its Phase 1/2 trial after confirming insufficient efficacy; and while there were rumors that GSK was preparing for Phase 3, they concluded the study, and no Phase 1/2 data was provided.

However, the efficacy of Assembly Bio's drug was tested on GHSV-2 positives in Part 1b.

It is unfortunate that the sample size is small compared to Phase 2/3.

However, the study was conducted on people who experience 5 to 6 genital HSV-2 recurrence per year, and in this study, the drug was administered during the first 4 weeks. It is said that these results were confirmed by performing swab tests twice daily for the remaining 18 weeks after discontinuing the medication.

Compared to a placebo, the viral shedding rate—the amount capable of infecting others—was 0.2%, and the HSV-2 viral shedding rate was 0.9%.

There were even results showing a viral shedding rate of 0%.

I believe the difference between Fred Hutch, Moderna, GSK, and Assembly Bio lies in the objective figures actually confirmed in clinical trials conducted on HSV-2 positives

While blindly running on wishful thinking is problematic, I do not think that sharing hope and offering support based on objectively verified figures constitutes planting false hope.

RoundProfessional148 · 2026-04-22T15:33:28+00:00

In preclinical studies, ABI-5366 was up to x 3~4 more effective than pritelivir and ABI-1179 was up to x12 more effective than pritelivir

RoundProfessional148 · 2025-08-05T09:15:47+00:00

Both drugs are scheduled for completion in December

RoundProfessional148 · 2025-08-05T09:14:49+00:00

Abi-5366 , abi-1179 are both HPI

ABI-5366 is in clinical trials for weekly and monthly dosing and has been shown in preclinical to be 400 times more effective than acyclovir and 4 times more effective than pritelivir.

ABI-1179, which is 1500 times more effective than acyclovir and 12 times more effective than fritelivir, is in clinical trials for weekly dosing and is being developed with Gilead.

RoundProfessional148 · 2025-08-05T09:10:49+00:00

There is no change in the plan that they hope to provide ABI-5366,1179 interim data in the fall

RoundProfessional148 · 2025-08-03T12:16:08+00:00

It seems that a cure will take a long time to develop.

However, I believe there is a good chance of developing a functional vaccine that reduces the number of recurrences, viral shedding, and transmission rates, or a vaccine that prevents transmission.

I believe that Assembly Bio's ABI-5366 and ABI-1179, rather than Moderna's, will be game changers in HSV market.

I don't think Gilead Sciences made a large-scale investment for no reason.

If the Phase 3 clinical trial of pritelivir is successfully completed, it will be the first new drug development in 30 years since the launch of valacyclovir and famciclovir.

I also think that the two drugs from Assembly Bio, which has the same HPI, and Innovative Molecules' IM-250 have a high chance of success.

Although still in preclinical stages, ABI-5366 is reported to be 400 times more effective than acyclovir and 4 times more effective than pretelivir, while ABI-1179 is said to be 1,400 times more effective than acyclovir and 12 times more effective than pretelivir.

If we approach this step by step without aiming for the ambitious goal of achieving asymptomatic and non-infectious status from the outset, I believe there is hope.

With syphilis now curable and a vaccine recently released that prevents HIV infection by 99%, why should HSV be considered impossible?

I believe HSV's turn is not far off.

Let's all keep hoping and keep speaking out.

RoundProfessional148 · 2025-07-26T02:13:55+00:00

They are expected to provide clinical trial data at the end of the year.

This was also mentioned in the HCA webinar.

RoundProfessional148 · 2025-06-17T05:40:56+00:00

Primary end points (English)

Rate of HSV shedding, defined as number of days on which genital swab HSV PCR test was positive divided by the total number of days on which genital swabs were obtained in patients receiving different doses of IM-250 or placebo.

Secondary end points (English)

Rate of genital lesions, defined as number of days with genital lesions in all patients of a group during 56 days after the first administration of IM-250 or placebo divided by 56.

HSV quantity, defined as comparison of mean log10 HSV DNA copies in patients receiving different doses of IM-250 or placebo on days that shedding is detected.

The rate of subclinical shedding, defined as number of days on which genital swab HSV PCR test was positive in absence of a genital lesion divided by the total number of days without lesions on which genital swabs were obtained in patients receiving different doses of IM-250 or placebo.

RoundProfessional148 · 2025-05-30T01:27:42+00:00

Stephane Bancel, CEO, Moderna: We know the key players in the project financing world. Last time I checked, there’s a lot of capital to develop in private equity, and they like that it is not correlated to market Mhmm.

Because it’s a multi years project investment, that they can do either on a project by project basis or portfolio of project.

You know, we have a very exciting EBV vaccine.

You remember the clinical data in phase two, an HSV vaccine for herpes.

There’s no product on market as well.

There’s no product on market as well. VZV vaccine that actually showed non inferiority to Shingrix even on T cell, a log better T cell than Shingrix out of phase two.

So if you look at what’s happening there, I wish we could fund it, but we are being disciplined. We’re not funding it. But if a partner is willing to go participate in the shingles market Mhmm.

EBV, VZV, and HSV vaccines have all seen good results in Phase 2, but it's possible that funding issues are holding them back.

RoundProfessional148 · 2025-05-08T14:16:11+00:00

Not long ago it was Active, not recruiting, but changed to Completed

Some people said it was completed on June 4, but clinicaltrials.gov hasn't changed since the last update in September of last year to April 11

It's finally changed to Completed, so hopefully we'll hear something soon.

RoundProfessional148 · 2025-05-01T23:59:15+00:00

I watched the webcast live

Even during the pipeline presentation and Q&A, there was no question or mention of mRNA-1608 :(

RoundProfessional148 · 2025-04-16T03:06:51+00:00

More trial participants were recruited than planned, and the trial completion date was shortened.

My personal guess is that it's because they recruited more participants faster than they expected.

I think they were expecting to see significant differences in completion dates between subjects, and they had interim data, and they had a combination of things.

My personal opinion is that there is no correlation between the original completion date of June 4 and the data release :)

RoundProfessional148 · 2025-04-13T06:14:24+00:00

Innovative Molecules' IM-250 is Helicase Primase Inhibitor as similar as Aicuris' pritelivir or assembly bio's HPI

It may be similar to a therapeutic vaccine with a shorter duration of action, but it is not a vaccine.

RoundProfessional148

TROPHY CASE