Momenta Pharmaceuticals, Inc. (MNTA)

[investorgold2002]

"is some other fraction of the mixture that could also serve as a proxy - the only downside is the time it takes to prove it to yourself and then prove it to the FDA"

Yes finding another signature to prove equivalence.
The theory is like how pyro-gluco is being used MNTA as signature
for making equivalent copaxone there could be another hidden proxy.

In Lovenox:
Patent claim in dispute was for measuring(or testing methods for measuring) for eg: 1-6 anyhydro is the blocking patent claim
This 1-6 anyhydro was known to be present by innovator, Sanofi (USP monograph)
They also found P8 for the 1st time and measured p8. Bit surprised that they did not contest this(i think this was part of 2nd patent which was dropped)

In Copaxone:
They have indeed found a new proxy signature (pyro-gluco) for end product (No mention of this in USP monograph-So a new proxy). And pyro-gluco was resulting due to depolymerization parameters (see point 2 below)


So if you look at the MNTA science behind finding the signature....they

1. Find out all different chemical constituents of complex molecule. For eg: P8 was a new polysacharride found by MNTA in heparin

2. then identify which of those constituents result due to just starting material selection(polysacharride 8) and which are dependent on function
{1-6 anhydro-ring in lovenox
or pyro-glucu in copaxone both are due to depolymerization and associated parameters in that process}

This starting material to end-product signature and process to end-product signature is the KEY in figuring out "signature"

The question to ask is , if they have identified all the structural nuances that result in complex molecule
(due to starting mtl or process) , could there be another proxy?