Most of the data that is available for analysis is for dosages ranging from 200 mg to 400 mg. The average Topiramate dosage for the UK study where there were incidences of cleft lip was 299 mg.
There is not much data to analyze for low doses of Topiramate. Qnexna highest Topiramate level is only 92 mg. This level is much smaller than the dosages included in the UK study. It is less than half of the typical average dosage prescribed for Topiramate.
There are only 3 pregnacy registries worldwide: North America, UK and Australia. As a result:
(1) There is very limited data available worldwide for 100 mg Topiramate dosage, and its effect on preganices.
(2) What little data that is available will not take long to analyze.
(3) The true impact of 100 mg dosage on pregnacies will not be answered until post-approval of Qnexa.
In my opinion, FDA is satisfied with Vivus response in the Breifing Document to cardiovascular concerns, and all other concerns. Qnexa should be approved this year for all 3 dosage levels.
The cleft lip concern is the only remaining concern. There have been a few incidences of cleft lip with Topiramate, but the dosage levels were much higher (200 mg to 400 mg).
This is very good for Vivus, because Vivus does not want to restrict the use of Qnexa to "men and women above reproductive or child-bearing age". This would significantly limit the size of Qnexa's potential market and the overall value of Vivus shares.
The FDA is only making sure all I's are dotted and T's are crossed. The feasibility determination and a possible subsequent analysis of existing databases for 100 mg dosages, should not take too long.
Let's say I took a qnexa pill of the high dose variety (a dose for which Vivus is seeking approval). 10 minutes later I can't remember whether I took the pill or not since I had other things on my mind. I decide to take another pill. This means that I have roughly 200 mg topiramate pumping through my body. According to you, 200 mg showed a cleft-lip response. For this, if I were a woman and unknowingly pregnant my embryo would be at risk.
High-dose qnexa presents a high risk of cleft lip in developing embryos and is under FDA scrutiny for this reason. Even mid-dose should be explored.
agree with most of the assessments of Qnexa risk presented in this thread, EXCEPT for the (OREX supporters, who fear approval of Qnexa) negative, "Qnexa will never get approved" bashers who do not have anything to add to the discussion. The 100mg dosing study to determine IF there is a oral cleft risk cannot be done pre-approval (ethics) - this is why the FDA requested review of EXISTING data - so Qnexa will get a warning similar to Topamax, imo, indicating to physicians not to prescribe to preg/intend to preg women.
This drug works better than the competitors, so fear is a factor in posts from supporters of lorc or contrave, imo. WHEN Qnexa is approved, imo there will be some mutual exclusivity to marketing of Contrave or lorcaserin to the same patient population, and they will NOT be able to penetrate Vivus' share of this huge market. PLUS, they do not have Avanafil to fall back on.
All imo, of course...let the naysayers begin their retorts.
very informative--but since you were able to find this information,how and why did the fda ask for this study-if there is no info available??? are they that fat stupid and lazy? i think again that there is some other agenda that is preventing them from approving this drug.
If you are right about the 100mg. dose then VVUS should clarify this with investors. I do believe that what the FDA is asking for cannot prevent QNEXA from being approved as Topiramate is already approved at much higher doses. Could the FDA decline the use of Topiramate in much lower doses? If they did they would look like complete fools to the rest of the world.