Вопрос к залу: задача
Oct. 6th, 2013 05:44 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
imbg Попросили помочь с задачей. Я видать уже слишком стар - даже имея ответ, не могу понять способ его получения. Возможно, кто-то может прояснить ситуацию?
Задача на англ - попробовал ее перевести, но от этого теряется много деталей, т.к. я переводчик еще тот. Итак:
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Если кто может подсказать логику, по которой все эти цифры появляются, буду весьма благодарен.
Задача на англ - попробовал ее перевести, но от этого теряется много деталей, т.к. я переводчик еще тот. Итак:
Below is a description of expected probability of success, by stage, in the Pharma R&D pipeline.
Note: “Filing” is the process of submitting all of the clinical and safety evidence from Phase I, II, and III trials, and asking for regulatory approval to actually sell the drug.
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To break even (that is, to make the $150 million investment worthwhile), the value of the candidate drug that passes Phase II would need to increase to $540 million + $150 million = $690 million. This means, the probability of combined success in Phase I and II would need to increase by (150/540) = 28 percentage points.
So the current probability of Phase I and II, that is, 70% x 40% = 28% would have to increase by 28 percentage points, to 56%. In order to come up to 56%, Phase II probability would have to increase from 40% to 80% (70% x 80% = 56%).
This seems like a very big challenge, as an increase by 40 percentage points means that the current probability of 40% needs to double.
GlobaPharm believes that the likelihood of success of primary drug candidate can be improved by investing an additional $150 million in a larger Phase II trial. The hope is that this investment would raise the success rate in Phase II, meaning that more candidate drugs successfully make it to Phase III and beyond. By how much would the Phase II success rate need to increase in order for this investment to break even?
Note: The interviewer would tell you to assume that if the drug is successfully marketed and sold, it would be worth $1.2 billion (that is, the present value of all future profits from selling the drug is $1.2 billion).
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Answer would include the following.
Investment would need to increase the probability of success in Phase II from 40 to 80 percent (that is, increase of 40 percentage points). There are multiple ways to approach this calculation. One method is shown here:
If a candidate drug passes Phase II, then it has a 50% x 90% = 45% chance of being successfully marketed and sold. Since a successful candidate drug is worth $1.2 billion, a candidate drug that passes Phase II is worth 45% x $1.2 billion = $540 million.
To break even (that is, to make the $150 million investment worthwhile), the value of the candidate drug that passes Phase II would need to increase to $540 million + $150 million = $690 million. This means, the probability of combined success in Phase I and II would need to increase by (150/540) = 28 percentage points.
So the current probability of Phase I and II, that is, 70% x 40% = 28% would have to increase by 28 percentage points, to 56%. In order to come up to 56%, Phase II probability would have to increase from 40% to 80% (70% x 80% = 56%).
This seems like a very big challenge, as an increase by 40 percentage points means that the current probability of 40% needs to double.
**************
Если кто может подсказать логику, по которой все эти цифры появляются, буду весьма благодарен.
