Its interesting to look at the IP refer Methods and Compositions...

Its interesting to look at the IP refer Methods and Compositions for the Treatment of Cancer. We can learn a little from the following;
"[Omomyc] has been applied solely using a gene therapy approach. Indeed, Omomyc is a peptide considered too bulky and unfit for delivery to the desired cellular compartment."

The statement would suggest that 'natively possess' doesn't refer to its original composition. Perhaps its a reference to some tweaking which has occurred more recently. Laura Soucek made a presentation titled Preclinical validation of Myc inhibition by a new generation of Omomyc-based Cell Penetrating Peptides. Perhaps 'natively possess' refers to the new generation peptides. In a presentation to the 14th International Congress ASEICA in Madrid, Soucek simply states that Omomyc can function as a CPP.

It would appear that the new generation of Omomyc-based CPP's, while 'natively possessing' cell-penetrating activity do not yet appear to have provided the pharmacological solution. Perhaps it all could come down to whether the CPP having entered the cell, can escape the endosome.