The present invention relates to certain 3-phenyl-pyrazole derivatives of Formula (Ia) and pharmaceutical compositions thereof that modulate the activity of the 5-HT2A serotonin receptor and are useful, optionally in combination with other pharmaceutical agents administered separately or together, in the treatment of platelet aggregation, coronary artery disease, myocardial infarction, transient ischemic attack, angina, stroke, atrial fibrillation, reducing the risk of blood clot formation, asthma or symptoms thereof, agitation or a symptom, behavioral disorders, drug induced psychosis, excitative psychosis, Gilles de la Tourette's syndrome, manic disorder, organic or NOS psychosis, psychotic disorder, psychosis, acute schizophrenia, chronic schizophrenia, NOS schizophrenia and related disorders, and sleep disorders, sleep disorders, diabetic-related disorders, progressive multifocal leukoencephalopathy and the like.