Theralase Technologies Inc. V.TLT

Cancer free patients

[Eoganacht]

I'm not sure if anyone has pointed this out but according to the new swimmer's plot there were:

2 patients still cancer free at 3 years after only one treatnent!
1 patient still cancer free at 2.5 years after only one treatnent!
1 patient still cancer free at 1.75 years after only one treatnent!
1 patient still cancer free at 1.25 years after only one treatnent!

So far all of our results have been obtained with no patient having had more than 2 treatments.

Clearly Ruvidar PDT is capable of completely eradicating NMIBC after only a single treatment. Why are some patients (about a third) not responding at all and why are some responders experiencing recurrence?

Not all of the patients who had no response or whose cancer recurred could have had upper urinary tract cancer. A substantial number probably had cancer cells which were deep enough below the surface of the urothelium that the green light did not reach them.

Theralase used green light, which has minimal penetration depth, to ensure there was no damage to the underlying healthy tissue.  I wonder if better overall results might not be possible in the future with further optimiztion - maybe with the judicious (targeted) use of deeper penetrating red light and the replacement of TLD1433 with Rutherrin,

[enriquesuave]

Good observation!  I suggested a while back that one possible way to treat non responders o and recurring patients is to use both IV Rutherin and intravesicle Ruvidar in combination in those cases to treat deeper or harder to reach cancer cells.  They would also be able to treat UTUC if they use Rutherin, via X-rays .

[Eoganacht]

I hope they are able to try this in the near future!

[CancerSlayer]

Powerful efficacy...correct me if I'm wrong, but it is my understanding that the most recent data presentation includes the first 12 patients treated, all of whom received at least one undertreatment & 4 of whom were withdrawn from the study due to the old criteria (unchanged CIS).  Under the optimized protocol, those 4 could have undergone a second/optimized treatment & possibly

[frebeach1]

Re Non Responsive high percentage  I asked Roger about the drop in numbers of CR patients but I also wondered why the high number of Non Responsive patients. I believe there is a fundamental problem at the cell surface that is preventing absorption of TLD1433 which only more research will discover. Dave at Bare Oaks.

[Eoganacht]

If a reason for non-responsiveness is insufficient take-up of Ruvidar by cancer cells then a switch to Rutherrin should be a big help, as cancer cells will not be able to distinguish Rutherrin from transferrin. But instead of taking in the iron they need to grow they will be getting the PS that will destroy them when activated by light.

[DJDawg]

One day we will know so much more. For example, I don't know how much they studied iron status of these patients. If you are iron deficient then the cancer cells will be much more avid. Maybe some of the great responders were iron low and that helped as the cancer cells grabbed the ruvidar. Cancer loves iron so much that there have been attempts to look at intentionally making patients iron

[CancerSlayer]

It would definitely be informative to review all of the patients' pre-treatment lab results to identify those who may have had anemia or a low iron status & look for any association between iron status (i.e. Hemoglobin or Ferritin level) & response rate.   At least theoretically, reducing a patient's iron level (via an already well-established/used therapy called chelation

[CancerSlayer]

Addendum:   Iron is an essential nutrient for a cancer cell's replication/growth.  This excessive hunger for iron causes an upregulation/increase in not only transferrin receptors, but also other transferrin receptor-independent mechanisms/proteins involved in iron uptake by cancer cells.  Therefore, having a low iron environment has the potential to increase either Rutherrin

[2b7f6fab]

Conversely, I wonder how many people with cancer have iron overload, like hemachromatosis?  My younger brother had hemachromatosis and was the first of my brothers to development prostate cancer.

[riverrrow]

A brilliant concept!  Ensure the patients are iron deficient before Ruvidar treatment.  Once Ruvidar is approved this would make for a great study.  Actually, pre treatment iron levels should be performed on all newly enrolled patients.

[riverrrow]

Imagine if a simple tweek like creating iron deficiency would result in a CR of 100%!

[Gooseybear]

As someone who has had NIMBC cancer and 20 BCG treatments and am 3 years NED with no additional treatments, I bet if someone at the FDA experienced this, they would approve TLTFF treatments in a heartbeat.