Competition, page-17

Hi,
Hopefully not too much info below, but Ga68-PSMA-11 and Lu177-PSMA-I&T/617/J591 are not strictly a pure theranostic pair.

Both TLX 591 (Ga-68-PSMA-11) and Lantheus' DCFPyL bind to PSMA that is overexpressed in prostate malignancy and can be used to assess disease burden and suitability for PSMA based radioligand therapy (RLT) - TLX calls this MTR (molecularly targeted radiotherapy).

The major PSMA radioligands for therapy are Lu-177 synthesised with PSMA-I&T (ABX product) or PSMA-617 (Novartis).
These ligands do NOT have the same molecular structure as PSMA-11, they have different chelators (the link between the ligand and the radioactive metal) so none are a direct theranostic pair.
The I&T stands for imaging and therapy, and it is possible to synthesise Ga68 with I&T, which in case would be an EXACT theranostic pair (the exact same I&T ligand would be used to carry the Ga68 for imaging and Lu-177 for therapy).
No one really images with it though.

In practice, since DCFPyL and Ga68-PSMA-11 both have the same target, they can both be used as a measure of PSMA expression in disease and therefore both can be used to assess suitability for Lu177-PSMA therapy as well as response.

BTW, TLX591, or the J591 antibody, is completely different - since it is an antibody that will bind to PSMA via a different mechanism.

FWIW, I think the incoming battle is in the USA - Ga68-PSMA-11 vs DCFPyL.
Ga68-PSMA-11 is the more well studied isotope but the real limitation is that generator yields are not high (2-3 patients per yield, only 2-3 elutions per day).

DCFPyL is becoming more studied (recent prospective trials using DCFPyL proving its utility in primary staging and PSA relapse - OSPREY and CONDOR Trials - Evaluating F-18 DCFPyL PSMA Imaging for Prostate Cancer - Michael J. Morris (urotoday.com)) and has the advantage of being F18 based, meaning the number of doses that can be generated are limited by the amount the cyclotron produces (depends, but could be in the order of 20-50 times more than a single Ge-Ga generator per day).

I don't know who definitely will win in the USA, but the demand for PSMA PET will rise exponentially there, so I can see the potential for both TLX and LNTH as commercial producers.
Lots of upside with PSMA imaging and therapy to come, TLX will hopefully grow with the demand. GLTAH