Cross-over Study: After the 3rd month on-site evaluation (12 weeks post P1), during the same visit, the subject will proceed to the cross-over study. At this time, the patient will have the option to receive a repeat subcutaneous injection of the cross-over agent. If they desire one, a subcutaneous injection of the cross-over agent will be performed at that same visit. If they wish to defer the repeat injection, they will be contacted and asked every 4 weeks - between 12 weeks and 24 weeks post P1 (no subject will receive P2 after week 24) if they would like to have the subcutaneous injection of the cross-over agent. If they desire one, a repeat injection will be scheduled for the following week.