Agitation in Alzheimer's Disease - An Unmet Need

There is not an FDA approved drug for Agitation in Alzheimer's disease.  This unmet need has seen an increase in clinical trials recently.  Below are a few companies that are either in, or entering into a clinical trial for agitation in Alzheimer's Disease with various drug candidates.

AVP-786                                      
Avanir (owned by Otsuka) is running two phase 3 clinical trials for the treatment of agitation in patients with dementia of the Alzheimer's type NCT02442765, NCT02442778.
In a phase 2 clinical trial with the primary endpoint being the NPI Agitation / Aggression Domain, a stastistically significant (p=.001) was achieved with the non-deuterated version of called AVP-923. The results and publication of that trial is here Avanir JAMA Publication.  The drug was generally well tolerated. The current clinical trials will complete July 2018.  In four years from the beginning of 2016, AVP-786 could be the first FDA approved drug for this indication, and reach commercialization in 2020.  The patent extends until 2030 in the U.S., and 2028 in the EU.

AXS-05                                           
Owned by Axsome Therapeutics, is a combination of Dextromethorphan / Buproprion.
The company expects to enter a clinical phase 2/3 trial in 2016.  
7-21-17: Axsome has now entered into a Phase 2/3 Dementia via Agitation with potential readout first half of 2020.  

4-27-20: Results of phase 2/3, CMAI p=0.010

Brexpiprazole                           
Owned by Otsuka, with a revenue sharing agreement with Lundbeck.  There are two phase 3 clinical trials for patients with agitation associated with dementia of the Alzheimer's type currently running NCT01862640, NCT01922258, with a completion date of around June 2017.  This drug could prove effective for this indication, but the drug, like it's predecessor Abilify, has a black box label.  Also, Otsuka chose to buy drug AVP-786 (via Avanir acquisition) for this indication, while two clinical trials with Brexpiprazole were over a year into progress.       
1-9-2017:  Both clinical trials are now active, but not recruiting participants.  There will be 12 weeks plus a 30 day follow-up period.  Participants that have completed the 12 weeks double blind trial, are eligible to enroll in a 2 month observational study. 
6-7-2018: Otsuka is taking another try with Brexpiprazole with this US only clinical trial to complete in December of 2020 NCT03548584.

Lexapro (Escitalopram)                           
4-17-2017: This phase 3 clinical trial with 15mg Lexapro (escitalopram) is being sponsored by John Hopkins School of Public Health (JHSPH) for patients with agitation associated with Alzheimer's disease. The clinical trial is here NCT03108846, and has a completion date of August 2022. This is the first of potentially two phase 3 clinical trials that may be required by the FDA prior to filing an NDA if the drug is effective.

ITI-007                                     
Intra-Cellular Therapies is planning on a phase two clinical trial in the first half of 2016 with ITI-007.  The company does not have any significant findings with the drug for this indication in prior clinical trials.  ITCI ran a phase 1/2 clinical trial primarily for cognition, as there were no patients that exhibited agitation at baseline.  The press release is here Intra-Cellular.  
6-28-16:  Intra-Cellular has now entered into a phase 3 clinical trial for Alzheimer's patients experiencing agitation here NCT02817906 with readout August 2018. Results: Terminated study.

Pimavanserin                        
12-12-2016:  Acadia has now entered into a phase 2 clinical trial for Alzheimer's patients experiencing agitation with their 5HT2A Pima here NCT02992132, with readout June 2019.
12-20-2016:  ACAD releases top-line phase 2 ADP data.  But does not break out the sub-category of the primary endpoint NPI-NH, such as agitation and aggression.  The company announced in their conference call, that agitation and aggression was no different than placebo group.

Bottom Line Update 12-21-2019:  AXS-05 and Escitalopram, are the two drugs that hold the most promise for their respective clinical trial for Alzheimer's Agitation. AXS-05 should have phase 2/3 readout in the first half of 2020, and Escitalopram in 2022. Thank you for reading.   

Nuplazid: FDA Safety Label

Acadia Pharmaceutical's completed their advisory committee meeting (ADCOM) on March 29th.  After receiving a positive review from the committee, the next issue to be determined will be the box safety labeling.  Below is wording from the FDA Briefing Documents.

This sample of patients compared to their appropriate control group demonstrates more than double the risk of serious adverse events (SAE) in the PDP6 trial population (Observed Risk of death or SAE is 2.38 times greater [95% CI 1.00 to 5.73, p=0.05]) for 34 mg Pimavanserin vs. placebo.

Let's have a look at a mortality black box label that many of the anti-psychotics currently carry, including the newly approved Rexulti (brexpiprazole) for Acute Schizophrenia and as adjunct for Major Depression Disorder. 

Increased Mortality in Elderly Patients with Dementia-Related Psychosis
Elderly patients with dementia-related psychosis treated with antipsychotic drugs are at an increased risk (1.6 to 1.7 times) of death compared to placebo (4.5% vs 2.6%, respectively). Although the causes of death were varied, most of the deaths appeared to be cardiovascular (e.g., heart failure, sudden death) or infectious (e.g., pneumonia) in nature. REXULTI is not approved for the treatment of patients with dementia-related psychosis.

I think the above is a likely label scenario for Nuplazid.  In addition, the FDA may advise Acadia to run a phase 4 confirmatory clinical trial as part of approval.  

Bottom Line:  Acadia has completed some nice pre-marketing research for Nuplazid, and found that a black box warning label was not high on the list of doctors when deciding whether or not to prescribe this drug.  In other words, they would still prescribe the drug, as the best alternative for an unmet need regardless of the safety label, as Nuplazid has shown in clinical trials to not contribute to motor impairment.   May 1st, is the scheduled day that the FDA should approve the drug.  Thank you for reading.

ACAD: Acadia Pharmaceuticals ($22.94)

Just released today, Acadia Pharmaceuticals has started a Phase 2 trial for ADP (Alzheimer's Disease Psychosis).  The press release with the fine details is below.  This trial will be conducted in London England.

The Phase II feasibility trial, referred to as the -019 Study, is a randomized, double-blind, placebo-controlled study designed to examine the efficacy and safety of pimavanserin in about 200 patients with ADP. The study is being conducted through a large network of research care homes established as part of the National Institute for Health Research (NIHR) Maudsley Biomedical Research Unit. Following a screening period that includes brief psycho-social therapy, patients will be randomized on a one-to-one basis to receive either 40 mg of pimavanserin or placebo once-daily for 12 weeks. The -019 Study will assess several key efficacy endpoints, including use of the Neuropsychiatric Inventory - Nursing Home (NPI-NH) scale to measure psychosis (hallucinations and delusions), agitation/aggression, and sleep/nighttime behavior, as well as use of the Cohen-Mansfield Agitation Inventory - Short Form (CMAI-SF) scale and the Alzheimer’s Disease Cooperative Study - Clinical Global Impression of Change (ADCS-CGIC) scale. Key efficacy endpoints will be based on the change at week six from baseline. The study will also assess additional exploratory endpoints, including the cognitive status of patients using the Mini-Mental State Examination (MMSE) scale, and the durability of response to pimavanserin through twelve weeks of therapy.

About Alzheimer’s Disease Psychosis

According to the Alzheimer’s Association, 5.4 million people in the United States are living with Alzheimer’s disease. While the criteria for diagnosing Alzheimer’s disease are mostly focused on cognitive deficits, it is often the psychiatric and related behavioral symptoms that are most troublesome for caregivers and lead to poor quality of life for patients. An estimated 25 to 50 percent of Alzheimer’s patients may develop Alzheimer’s disease psychosis (ADP), which is commonly characterized by disturbing visual hallucinations and delusions. The diagnosis of ADP is associated with more rapid cognitive and functional decline and institutionalization. There currently is no therapy approved for the treatment of ADP in the United States.

Study Collaboration   “We are delighted to pursue this clinical study in collaboration with Professor Ballard and King’s College London,” said Roger G. Mills, M.D., ACADIA’s Executive Vice President of Development and Chief Medical Officer. “We believe that their unique clinical research infrastructure and expertise will provide access to a pool of well-characterized ADP patients and enable the use of a small and geographically-focused group of highly trained raters, which we expect to enhance study precision.”

Bottom Line:  ACAD has given this phase 2 trial for ADP every chance of success by working with Clive Ballard and the King's College London.  The study will be a small geographically focused group of highly trained raters which should enhance the study precision.  Thank you for reading.