Replies to post #75252 on Innovation Pharmaceuticals Inc (IPIX)

[biodoc]

loanranger, it is important to see that there is an early clinical response to treatment, regardless of the antibiotic regimen. That is, any effective treatment should be working in the first couple of days.

FDA has published a guidance paper that talks about primary and secondary endpoints for ABSSSI trials (see bottom of page 6):

http://www.fda.gov/downloads/Drugs/.../Guidances/ucm071185.pdf

Note that the secondary endpoint is complete resolution after 7-14 days.
Does this answer your question?

[noretreat]

We don't have the data for that (yet). All we know is B met the primary endpoint and was the statistical equal of Daptomycin at that point. Unless someone knows something I don't, your question cannot be answered until more information is available.

A single dose regimen has been selected for phase 3 and plans are being made to move forward. We also know from an earlier PR that all 4 arms combined had a better response at 7 days in the p2b than the p2a. While I would feel more comfortable with data in hand, it may be a while before we get to see it.

[TheHound]

Wouldn't that comparison be defined by the secondary outcome measures?

[BonelessCat]

I was waiting to see if NR could answer your question, but I see he only referred to the data not yet released.

The 48-72 hour 20% reduction is a measure of immediate response in critical cases of ABSSSI. Using the word "critical" I'm referring to the nature of ABSSSI as an uncontrolled infection that when untreated results in further complications, possible loss of limb or even life. An effective antibiotic must stop the spread of the infected area and reduce it by the minimum 20%. Drugs that don't show a quick response to treatment put the patient at continued risk, even if the response is greater after 7 or 10 days. One would not want to administer a drug that allowed continued infection with no subsidence within 3 days even if it were eventually 100% effective. Too many complications from infection remain in play without a significant response in less than 3 days.

The second question you ask regarding 2/3 treatment verses 2/7 or 3/7 is irrelevant to the two drugs. The number of doses has far less to do with sustained response with each dose and more to do with the elimination of the infection. Daptomicin requires 7 days and 7 doses to achieve elimination of the bacterial infection in 98% of people with a nearly zero chance of the infection returning. Brilacidin maybe requires one, though 3 seems certain, for sustained response and a lowest possibility of returning infection.

When a doctor prescribes antibiotics and warns the patient to take all the medicine, it's because most infections respond quickly to the antibiotic and patients may even feel completely cured before the prescription is complete, stop taking the final few doses and then relapse. This possible relapse in spite of appearing successful is the case with Daptomicin. By the 3rd administration the infection is responding rapidly to treatment. The problem is sustained response and elimination any residual bacterial matter still active and might cause relapse.