We are developing iloperidone for the treatment of schizophrenia, bipolar disorder and other psychiatric conditions. In four short-term and three long-term trials comprising over 2,500 patients, iloperidone demonstrated efficacy and reduced side effects relative to current antipsychotic drugs. We have submitted an NDA for FDA review. If iloperidone obtains regulatory approval, we believe it will represent a therapy for schizophrenia with distinct advantages over currently available drugs.
Limitations of current treatments
The treatment of schizophrenia remains challenging because currently approved antipsychotics often induce serious side effects and offer only modest and occasional efficacy. Side effects include weight gain, diabetes, extrapyramidal symptoms, hyperprolactinemia, increased somnolence and cognition difficulties. The side effect profile and modest efficacy of currently available antipsychotics result in poor patient compliance to their prescribed drug regimen. Consequently, there remains a high degree of dissatisfaction with atypical antipsychotics among physicians and patients. The recent CATIE (Clinical Antipsychotic Trials of Interventional Effectiveness) study, conducted by the National Institute of Mental Health and reported in The New England Journal of Medicine demonstrates this. It showed that 74% of patients taking antipsychotics discontinued treatment within 18 months.
Potential advantages of iloperidone
In addition to the efficacy observed in clinical trials to date, our experience with iloperidone thus far suggests that the compound may provide benefits to patients beyond those provided by currently available drugs:
- Safety. Short and long-term safety trials have shown that patients who used iloperidone had reduced side effects relative to currently available antipsychotics. Iloperidone was associated with low weight gain, no induction of diabetes, low extrapyramidal symptoms, no akathisia, no hyperprolactinemia, low incidence of sleepiness and low negative effects on cognition relative to placebo. Iloperidone has been found to be associated with a prolongation of the heart's QTc interval to an extent similar to that of Geodon®.
- Extended-release injectable formulation. We are developing an extended-release injectable formulation of iloperidone, which only needs to be administered once every four weeks and which we believe will be a compelling complement to our oral formulation for both physicians and patients. It has completed a two-month Phase I/IIa safety trial in schizophrenia patients, in which it demonstrated the benefit of consistent release over a four-week time period with no greater side effects relative to oral dosing.
- Unique tool to end "trial-and-error" prescribing. Based on our retrospective analysis of prior clinical data, we have determined that certain patients may be more likely to respond to iloperidone and to enjoy better treatment results relative to the general schizophrenia patient population. These patients have a common mutation of a gene linked to central nervous system function, that is estimated to occur in approximately 70% of schizophrenia patients. A genetic test which we developed and used in our current Phase III trial confirmed this correlation.