Anne-Marie Duliege
Analyst · Piper Jaffray
Thank you, Raul. As Raul stated earlier, we have continued our analysis of results from the FIT Phase 3 clinical program. Overall, we believe that the predictable efficacy profile of fostamatinib combined with the safety profile will make fostamatinib, if approved and a trusted treatment option for those patients with chronic ITP that are in need of [indiscernible] therapy. This data will be presented to the FDA in the new drug application that we're currently preparing. Fostamatinib's unique mechanism of action provides a potential benefit to people with chronic ITP. As a reminder, fostamatinib is a SYK inhibitor and targets the underlying cause of ITP. SYK kinase is a key player in the immune system destructions of platelets in ITP. ITP patients can have platelet counts that for below 30,000, the level at which they are generally considered at risk for spontaneous or trauma induced hemorrhage. And chronic ITP is difficult to treat disease. This patient population is very heterogeneous, so it is hard to predict which patient will respond to which of the currently available treatment, if any. There are approximately 60,000 to 125,000 patients with chronic ITP in the U.S. and it qualifies as an orphan disease. Turning towards the slide presentation, I will now review some of the key data points related to fostamatinib in ITP. Let's look at Slide 10, the FIT Phase 3 program consisted of two identical placebo control studies, 047 and 048, combined 150 adult patients with chronic or persistent ITP were enrolled with 49 of them assigned to placebo. Patients indeed were randomized into fostamatinib or placebo in a two to one ratio and then dose for up to 24 weeks. The primary endpoint was the achievement of the stable platelet count equal to greater than 50,000 per microliter on at least four of the last six clinic visits from which 14 to 24. At the conclusion of the participation in either of the two studies, patients were invited to enroll in an open label long-term extension study 049 where all patients received fostamatinib. Moving to Slide 11, overall the population suffered with very severe chronic ITP as reflected in, one the median platelet count at baseline of 16,000 per microliter, and two a median duration of ITP of 8.5 years prior to study entry. And all the subjects had received one or more prior ITP treatment option with the majority of them being steroid, 35% of them had a splenectomy and close to 50% of patients had tried TPO agent. Moving to Slide 12, previously we announced the results of both the FIT 047 and 048 studies, which showed a consistent stable platelet response of plus 18% in the fostamatinib group in both studies. With those studies complete, we have all the data in order to provide additional insight. As Raul explained when patients respond to fostamatinib, they respond quickly with a robust and sustained response. If you look at this chart on Slide 13, it shows how quickly the median platelet numbers to the fostamatinib responder in green began to climb within a few weeks and the platelet counts continue to rise to approximately 100,000 per microliter where they held steady through the balance of the 047 and 048 studies. Turning now to Slide 14, during our post-op data review for the NDA filings, further analysis was done to characterize fostamatinib in patients who may not meet the very high bar set for the stable response criteria in 047 and 048, but who may have achieved a meaningful platelet count or benefit. We specifically look at patients who had achieved at least two consecutive platelet counts over 50,000 per microliter during the trough without rescue. Initially defined that transient, these responders in fact had a platelet response with a median of approximately 50,000 per microliter overtime and so we have renamed these as intermediate responses, intermediate between no response and a stable response. There were 11 of these patients in the fostamatinib group and none in the placebo group. By contrast, the non-responders and the placebo patient median platelet count remained at or below 30,000 per microliter over time. So, when adding the stable and intermediate response rate, the overall response rate for both studies again shown on this slide 14, is 29%, 29 out of 101 patients for the fostamatinib group compared to 2% for placebo, and the difference is of course highly significant at 0.0001. But the important point is that the primary endpoint is the stable response, this is the predefined endpoint in our NDA submissions. The intermediate response is the post study analysis that supports the clear treatment of set of fostamatinib. Coming back to the analysis of the primary endpoint we conclude on Slide 15 that fostamatinib works effectively for certain ITP patients and the benefit was consistent across all subgroup analyzed including exposure to TPO agents previously, this blood platelet producing booster who have limited treatment options remaining. Moving to Slide 16 with over 5,000 patients worth of data including previous trial in RA, we feel comfortable about the safety profile of fostamatinib. The results during the placebo control studies are summarized in this table. Adverse events in the fostamatinib group in studies 047 and 048 were generally mild or moderate with GI gastrointestinal, blood pressure and LFT adverse events reported most frequently. All adverse events are manageable and reversible. Of note, there were more assays of bleeding in the placebo group then in the fostamatinib group. In the fostamatinib group inside these assays, the serious adverse events of bleeding occurred in the non-responders and not in the stable or in the intermediate response rate. Now the next three slides describe our ongoing open label long-term extension study also known as 049. All patients in the FIT 047 and 048 studies were invited to enroll in 049 wherein they had completed the participation of the parent test. When the data was collected up to in September 2016 which is the interim analysis of this long-term extension, there were 123 patients enrolled and receiving fostamatinib in 049. 17 stable platelet responders from 047 and 048 studies had enrolled into the 049 study and the median platelet count for those responders were over 100,000 per microliter after a total median exposure to fostamatinib of approximately 16 months. This is actually a very good result because it shows that for the majority of patients have better response. This response is sustained overtime. In the 049 study, we also assessed the percentage of patients who were initially randomized to the placebo group in the parent study and responded in the 049 Study. There were nine of these patients and 9 out of 41, is 22% with a P value of 0.0078. So, 22% of the former placebo patients now newly exposed to fostamatinib for a minimum of 12 weeks achieved a prospectively defined stable response. And this result is consistent with the response rate of 18% achieved in the parent trial. So our analysis of the FIT Phase 3 study will continue, and we plan to share additional information at upcoming scientific meetings and in publication. On Slide 21, we want to remind you of our regulatory path forward where using the current available data to prepare the NDA dose here for fostamatinib in ITP to provide to the FDA. Our submission could potentially lead to an FDA Advisory Committee review later in the year and of course we will continue to communicate about all regulatory milestones. Moving to Slide 22, Raul mentioned our study of fostamatinib in IgA nephropathy the most common glomerulonephritis worldwide. Because it causes inflammation and scarring of the kidney, people with this rare condition are at risk of serious complications from kidney dysfunction including high blood pressure and renal failure. The first cohort in the Phase 2 study, outlined on Slide 23 was completed at various centers throughout Asia, the US and Europe. This cohort evaluated the efficacy, safety and tolerability of lower dose of fostamatinib 100 milligram BID with 26 patients assigned to fostamatinib and 12 patients to the placebo actually randomized, and the measure of change in proteinuria renal function and histology which were the efficacy parameters. In fact, the primary efficacy endpoint was the main change of proteinuria from baseline to 24 weeks and it is shown on Slide 24. The study found that at 24 weeks fostamatinib was well tolerated with no new safety signal detected. The initial data suggested trend towards a greater reduction in proteinuria in fostamatinib-treated patients relative to placebo. Given this initial data, we began enrollment of cohort 2. Rigel expects that the second cohort evaluating a higher dose of fostamatinib 150 milligram BID for IgA nephropathy will finish enrollment in 2017 with results in 2018. I will now turn the call over to Ryan to provide our financial reporting.