more DD for DNDN
Re: The Future of Provenge Use
<I say forget PSA, forget androgen therapy, definitely forget watchful waiting. Here's the future: a patient has a prostatectomy for localized prostate CA. Every 6 months he undergoes RTPCR screening of his serum for PSA (looking for evidence of metastasis). If his PCR screen turns positive, he starts treatment with provenge, followed by yearly booster shots. >
The P-11 or PROTECT phase-3 trial is testing this although at a slightly later stage when the PSA level has risen enough for patients to start hormone therapy. Initial results included stat sig prolonged PSADT and a 25% increase in Time to Metastasis. Unfortunately (for the trial, not for patients), metastasis could take years so the final data may be still a few years out. But when that comes, I do expect the result to be spectacular for Provenge by the hypothesis that the immune system once primed is great at mopping up residual disease.
If Provenge can be used to replace hormone therapy that would be of great benefit to patients. Androgen ablation caused side effects such as loss of cognitive functions, sex drives, feeling of weakness, depression etc. A recent research finding showed that even though patients may survive longer on it they also die more often of other diseases likely due to the side effects.
The ADPC market is about 4-5 times larger than the AIPC market so that would be a huge market expansion. The main issue with P-11 is that it isn't a registration trial so it is unclear whether the FDA will accept an sBLA based on it. Hopefully, after approval, a new round of trials can be conducted either by the company or other research groups to provide corroborative evidence when that time comes.
