But we still expect there to be a linear shaped uptake curve. Unlike some other rare diseases where there might be an early access program where you might create a bolus of patients, that’s not really what we had here. As Kathie described, there is an open-label extension in LILAC-2 and we do expect the majority of those patients to transition over to commercial drug, but that’s going to be a function of and subject to their individual payer access time lines by geography. I think your second question was around pricing. So we are not going to disclose pricing before approval to levels that we can add a little bit of context. With rare disease therapies, there tends to be an established range of prices and there are several elements that tend to contribute to where products tend to price.
The first is the severity of the disease. The second is the level of unmet medical need and the ability of a product to address those needs. And then third, is the relative rarity of the disease itself. So if we are thinking about Rett syndrome in particular and then the value of trofinetide, Rett syndrome is a very devastating disease. It causes substantial disability to patients and it disrupts the lives of families and caregivers who provide essentially a round-the-clock care to patients. The unmet medical need is equally high here with no approved therapies available to address the core neurodevelopmental symptoms of Rett syndrome, creating a critical void that needs to be filled. Given the robust response seen in our Phase III studies for trofinetide, it is potentially poised to address that unmet need.
And then finally, there is the relatively small prevalent population estimated at 6,000 to 9,000 in the United States with the 4,500 or so currently diagnosed and treated patients. So with that background, I think you should expect us to price trofinetide as the first and only therapy poised to address that high level of unmet need and to ensure broad access for patients and families who stand to benefit from treatment.
Operator: Thank you. One moment for our next question. Our next question comes from the line of Charles Duncan from Cantor Fitzgerald.
Charles Duncan: Yes. Good afternoon. Thank you for sharing the LILAC information that you did today. I guess I am wondering if you had any, I guess, patterns that you recognize with regard to discontinuations and/or diarrhea specifically with regard to timing and severity, and do you anticipate actually formally engaging with the agency regarding Rett?
Steve Davis: Yeah. Kathie, do you want to take that question?
Kathie Bishop: Hi, Charles. Thanks for the question. With regards to the pattern of discontinuation due trofinetide — due to diarrhea associated with trofinetide, I will say that the pattern discontinuations in LILAC was very similar to that in LAVENDER and that we have a very similar discontinuation rate within about the first three months and then a smaller rate after that. And as I mentioned on the call, in the subsequent study, LILAC-2, we have a very low discontinuation rate and none do the diarrhea to-date. So one pattern that emerges from this is that the longer you are in trofinetide, longer you are able to stay on it. As I mentioned, it is also notable, though, that in the early years of these trials, they did extend over several years, we did not have the diarrhea management plan in place.
So as we think ahead to launch, we are instituting that plan and Brendan is there to provide many resources to caregivers and the patients to manage the diarrhea to be able to give them on drug.
