AUA 2009: Memantine

[webslave]

(Note: this is an abstract from a conference, not a published study.)

Memantine in the Alleviation of Symptoms of Chronic Pelvic Pain Syndrome: A Randomized, Double-Blind Placebo-Controlled Trial

Authors: Jordan D Dimitrakov*, Boston, MA; Jean Chitalov, Ivan Dechev, Plovdiv, Bulgaria

Introduction and Objective: The etiology and underlying pathogenetic mechanisms of chronic pelvic pain syndrome (CPPS) remain elusive. The hallmark of the syndrome is chronic pelvic pain in the absence of identifiable underlying pathology. Recently, CPPS has been conceptualized as a central pain syndrome and N-methyl-D-aspartate (NMDA)-receptor mechanisms have been implicated in the generation of symptoms of CPPS. The objective of this study was to evaluate the efficacy and safety of memantine, a noncompetitive N-methyl-D-aspartate (NMDA)-receptor blocker in the alleviation of CPPS symptoms. Methods: 170 men with CPPS were randomly assigned to receive either memantine 20 mg/day or placebo for 1 year. CPPS was diagnosed in accordance with the CPCRN criteria. All patients provided written informed consent and the study was approved by the insitutional review board. The primary outcome was alleviation of pain at 6 months based on the NIH-CPSI pain domain scale. Secondary outcomes were patient-reported improvement in GRA, voiding and quality of life scales of the NIH-CPSI. Results: The study is ongoing and 1-year results will be presented at the AUA meeting. At 6 months, patients in the memantine group reported significant improvement in pain, GRA and quality of life as compared with patients in the placebo group (77% vs. 16%, P<0.001). No difference was noted between the placebo and treatment groups in the voiding subscale of the NIH-CPSI. Side effects were minimal and included dizziness (7%), headache (5%) and tiredness (1%). Conclusions: Memantine appears safe and effective in the alleviation of symptoms of chronic pelvic pan syndrome in men. Future studies should evaluate long-term treatment outcomes in larger patient cohorts.

[carld]

Interesting...

[kpbos]

What's 'GRA'?

[webslave]

Global response assessment (a 7-point scale ranging from markedly or moderately improved to markedly worse).

[J Dimitrakov]

Thanks for featuring this report. There will be additional discussion of the implications of the study, results and longer follow-up of patients. I will post the link as soon as it becomes available

Best,
JD

[ramana]

Thank you Dr Dimitrakov for your efforts. What is the next step. I do not understand the process that happens from the point when a drug has been identified to be useful in a particular ailment to it becoming mainstream in the management of the ailment. Can you please throw some light on this issue? Thanks

[J Dimitrakov]

Thank you Dr Dimitrakov for your efforts. What is the next step. I do not understand the process that happens from the point when a drug has been identified to be useful in a particular ailment to it becoming mainstream in the management of the ailment. Can you please throw some light on this issue? Thanks

Thanks, ramana.

Next step would be a Phase III trial which is a large-scale, preferably multi-center, randomized double-blind controlled study. A general explanation of this type of study cn be found here:

http://en.wikipedia.org/wiki/Clinical_trial#Phase_III

Naturally, one of the biggest challenges we will face is patient heterogeneity - i.e. the drug will not work for everyone with CPPS. Therefore, the onus is on us to define a patient subst for which this is effective

Best,
JD

[uksufferer2]

hi,
very interesting!

how does this fit in with the study around lateonset CAH if at all? .... do the two papers support each other in an overall cause or do they suggest 2 different causes?

[J Dimitrakov]

hi,
very interesting!

how does this fit in with the study around lateonset CAH if at all? .... do the two papers support each other in an overall cause or do they suggest 2 different causes?

This is a treatment study which did not look for a "cause' for CPPS. It tested a specific treatment approach based on a specific underlying hypothesis.

The CYP21A2 study was a "biomarker" study which looked for a specific pattern consistent with a hypothesis regarding the underlying basis of the condition. As we have been discussing in the forum over the years, CPPS is a heterogeneous conditions and there are different mechanisms at play even in the same individual at different points in time.

Best,
JD

[uksufferer2]

thanks for the reply

This is a treatment study which did not look for a "cause' for CPPS. It tested a specific treatment approach based on a specific underlying hypothesis.

what is the underlying hypothesis for the memantine treatment ? or do i need to wait for the full article to be published?

thanks

[J Dimitrakov]

You can read the abstract or follow the AUA discussions.

Best,
JD

[webslave]

"There are a couple of messages for the clinician," Dr. Dimitrakov said. "The main message is that we need to see a larger study in women with CPPS to evaluate this medication in more detail. The second is that in our hands, this medication appears safe and effective, with minimal side effects. Finally, this is a medication that actually works on a subset of patients. It would be unrealistic to think that a medication is going to be effective in all patients with CPPS."

From http://license.icopyright.net/user/view ... M5OA%3D%3D

[J Dimitrakov]

"There are a couple of messages for the clinician," Dr. Dimitrakov said. "The main message is that we need to see a larger study in women with CPPS to evaluate this medication in more detail. The second is that in our hands, this medication appears safe and effective, with minimal side effects. Finally, this is a medication that actually works on a subset of patients. It would be unrealistic to think that a medication is going to be effective in all patients with CPPS."

From http://license.icopyright.net/user/view ... M5OA%3D%3D

Thanks for posting this, Webslave. For those interested, here's a podcast that expands on the study (starts around 06:10)
[[Webslave edit: see post below for exact audio (smaller download)]]

http://community.modernmedicine.com/_AU ... 79.html?b=

Best,
JD

[webslave]

This is the extract you want to listen to:
memantine-dimitrakov-2009.mp3

[critthinker]

Dr. Dimitrakov,

Do you have any updates on this drug's progress?