Akshay K. Vaishnaw
Analyst · Canaccord Genuity
Thanks, John, and hello everyone. We've indeed continued to made great progress with our pipeline of investigational RNAi therapeutics. Let me begin with our RNAi therapeutic programs for the treatment of TTR-mediated amyloidosis, or ATTR amyloidosis. As you know, we have 2 product candidates in this area. Patisiran, our lead program is aimed at the treatment of ATTR amyloidosis patients with familial amyloidotic polyneuropathy, or FAP. Patisiran is in a Phase III trial called APOLLO, and we now have over 40 sites in over 15 countries open. Revusiran is our most advanced subcutaneously administered RNAi therapeutic in the clinic today and is focused on the treatment of ATTR amyloidosis patients with familial amyloidotic cardiomyopathy, or FAC. This product candidate is also in a Phase III trial and that trial is called ENDEAVOUR. Let's turn to some of the data generated from both these programs, and I'll start with results we presented in April at the AAN meeting, where we presented interim 12-month results from our ongoing Phase II OLE study of patisiran in patients with FAP. At 12 months, we showed a mean 2.5-point decrease in the modified neuropathy impairment score, or mNIS+7, in 20 patients with data available for the current analysis. As shown on Slide 11, this decrease in neuropathy progression compares favorably with the 13- to 18-point increase in mNIS+7 at 12 months that can be estimated from historical data sets in untreated FAP patients with similar baseline characteristics. Importantly, there was a consistent effect across all the mNIS+7 subcomponents including more objective measurements. With the very important caveat that our results stem from an open-label study in a small number of patients, we're encouraged to see what we believe to be evidence for a possible halting of neuropathy progression after the first 12 months of treatment. Moreover, these data are very encouraging with regard to our APOLLO Phase III study, since the primary endpoint of this study is also the mNIS+7 neuropathy score. In addition, repeat dosing of patisiran achieved sustained mean TTR knockdown at the 80% target level, with the mean nadir of up to 88% TTR knockdown between doses and up to 96% TTR knockdown on an individual basis. This consistent level of knockdown gives us confidence in our potential to maintain knockdown throughout this Phase II OLE study and also in our APOLLO Phase III study since we're using the same dosing regimen. Finally, it is of mention that this is now what we believe to be the industry's best evidence to date, that RNAi can be sustained in humans over a long duration of treatment. And we've seen no evidence to date of tachyphylaxis or an immune-mediated clearance affect. Importantly, patisiran was also found be generally well tolerated in the study after 17 months of therapy, with no drug-related serious adverse events to date, and all 27% patients enrolled in the study continue to receive drug treatment. Of course, we'll be very interested to see how these results, including the mNIS+7 data, mature going forwards. And with these encouraging results in hand, we now look forward to sharing 18-month clinical results in late 2015. We also plan on discussing these results with regulatory authorities in the U.S. and EU, as they relate to potential consideration of our APOLLO Phase III study, and we'll update you if and when appropriate. Turning to APOLLO, I'm very pleased to say that this trial is proceeding well. As a reminder, APOLLO is a randomized, double-blind, placebo-controlled study designed to evaluate the efficacy and safety of patisiran in ATTR patients with FAP. And if successful, the study would support marketing authorization for patisiran in countries around the world. Primary endpoint of APOLLO is the difference in the change in mNIS+7 between patisiran and placebo at 18 months. As I mentioned earlier, this is the same neuropathy impairment score we're employing in our Phase II OLE study. We're also using the same dosing regimen APOLLO as we are in our OLE study. Furthermore, patients enrolling into the APOLLO study present with a broad range of neuropathy impairment, similar to the patient population in the OLE study. Accordingly, we view our OLE study, especially over time as an important indicator of what we might anticipate seeing for patisiran-treated patients in APOLLO. We're really pleased with the pace of enrollment in APOLLO, and we've guided that we would expect to file our NDA for this program in 2017, if the study is successful. Of note, the pace of our APOLLO study enrollment has been increasing since our 6-month OLE data was presented this past October, and we expect it to increase still further with the recent presentation of our 12-month OLE results. Let's now turn to recent progress with revusiran. At the American Oncology of Cardiology Meeting in March, we presented complete results from our Phase II clinical trial with revusiran in patients with TTR cardiac amyloidosis, where we showed robust knockdown of serum TTR of up to 98.2%, with weekly subcutaneous injections of revusiran. Revusiran was also shown to be generally well tolerated in these patients with advanced disease, demonstrating a safety profile that supports advancement into Phase III. These patients from the Phase II study are now rolling over into an open-label extension study, where they'll be able to receive revusiran for an extended period of time, similar to what we've done for patisiran. Of the original 26 patients in the Phase II study, we're expecting most to enroll into the Phase II OLE, and we expect to complete enrollment in the next couple of months. The OLE study will evaluate the safety and tolerability of long-term dosing with revusiran for up to 2 years, and we'll also measure effects of treatment towards a number of clinical endpoints including mortality, hospitalization, 6-minute walk distance in addition to cardiac biomarkers. We intend to report clinical data from this study about once a year with initial data in late 2015. We also reported recently on our FAC natural history study results. Its retrospective analysis evaluated disease progression in FAC patients and demonstrated a clear and robust decline in 6-minute walk distance over an 18-month period. Specifically, at 18 months, the mean decline in 6-minute walk distance was 140 meters. These findings give us confidence that our ENDEAVOUR Phase III trial of revusiran in FAC patients is appropriately designed to show the potential impact of TTR lowering on the co-primary endpoint decline from baseline in 6-minute walk distance of 18 months. In addition, these data provide context on our ongoing Phase II OLE study of revusiran. We continued enrollment efforts in our ENDEAVOUR Phase III trial with revusiran. This is a randomized, double-blind, placebo-controlled study, which we -- where we're looking at 2 co-primary endpoints measured at 18 months. One, being the change in 6-minute walk distance between drug and placebo, and the other being reduction serum TTR between drug and placebo. It's still relatively early in the study's initiation, and we'll provide more guidance on the study time line as enrollment continues during the course of this year. Finally, we're also pleased with the ongoing progress in our DISCOVERY screening study. DISCOVERY is being conducted at large number of centers with the goal of identifying TTR mutations in patients with heart failure and other risk factors consistent with FAC. We look forward to sharing some results from DISCOVERY later this year. I'd like to now move on to our latest progress with ALN-AT3 and RNAi therapeutic targeting antithrombin in development for the treatment of hemophilia and rare bleeding disorders. We view this is as a very exciting and innovative programs since antithrombin knockdown has the potential to rebalance the coagulation cascade in patients with hemophilia and other rare bleeding disorders, which should lead to enhanced thrombin generation, improved hemostasis, a possible disease-modifying effect, which we believe could result in possible functional correction of disease. At the Goring Coagulation Conference in January, we were pleased to present interim results from our ongoing Phase I trial, including what we believe to be initial evidence, that ALN-AT3 has the potential to correct the hemophilia phenotype. Specifically, in the second dose cohort at a very low dose of ALN-AT3 at 45 micrograms per kilogram, we've demonstrated up to 70% knockdown of antithrombin with effects lasting for months. Importantly, there was a statistically significant and up to 334% increase in thrombin generation. These changes in thrombin generation in severe hemophilia was as if we've transformed the disease to a mild hemophilia phenotype, where patients rarely bleed and do not require replacement therapy. We're also able to demonstrate encouraging effects on the whole blood clotting in one subject, showing results consistent with an improvement in the hemophilia phenotype. This subject also remained bleed free for a period of at least 47 days, while his self-reported annualized bleeding rate was 10 to 12 bleeds per annum. Of course, these are early results from our Phase I study, but in aggregate, we believe these results highlight the significant opportunity for ALN-AT3 as a possible functional correction of hemophilia. Indeed, we believe that a once monthly subcutaneously administered RNAi therapeutic that provides disease-modifying effects for people with hemophilia and other rare bleeding disorders could be transformative for patients. And we're pleased to report today that we're now transitioning our Phase I study to once-monthly dose cohorts. We've also announced today that we plan to present additional data from this ongoing Phase I trial in an oral talk at the ISTH meeting in June. Based on our ongoing enrollment, we expect this report will include results from about a dozen hemophilia subjects and expect to include data on tolerability, antithrombin knockdown, thrombin generation, in addition to preliminary assessment on bleeding frequency. Finally, we also are reporting today that we've completed our chronic GLP Toxicology Studies for ALN-AT3. These studies included a 9-month study in nonhuman primates, a 6-month study in the rat and a 6-month study in hemophilia mice. We'll report some of those details of these studies at ISTH, but we are very pleased with the results that they fully support advancement of the program into Phase III. Moreover, these are our company's first results regarding chronic tox studies for our ESC-GalNAc-conjugate platform. And with the caveats related to antithrombin as a target in this program, this results are certainly encouraging more broadly. Also during the first quarter and recent period, we made progress with ALN-CC5, a subcutaneously administered investigational RNAi therapeutic targeting complement component C5 for the treatment of complement-mediated diseases. Most importantly, we initiated a Phase I/II clinical trial with ALN-CC5. This study has been conducted in healthy volunteers and is evaluating the safety and tolerability of single and multiple subcutaneous doses of ALN-CC5. Secondary objectives include evaluation of clinical activity for ALN-CC5, as measured toward knockdown on serum C5 and inhibition of serum hemolytic activity. The study will then be conducted in patients with paroxysmal nocturnal hemoglobinuria, or PNH. Of interest, this part of the study will include an exploratory evaluation of the effects of ALN-CC5 on the levels of lactate dehydrogenase, an important measure of red blood cell hemolysis. We're very pleased to announce today that we plan to present initial ALN-CC5 data in mid-June in an oral talk at EHA. Data at EHA will be presented for the initial SAD part of the cohort -- SAD part of the study, where we'll get an early look at C5 knockdown and potential effects on complement inhibition. Of course, the most robust effect from complement inhibition will likely be fully realized with multi-dose administration of ALN-CC5, and we aim to have those data in late 2015. Finally from our Genetic Medicine STAr, we recently filed and received approval for our clinical trial application, or CTA, for ALN-AS1, a subcutaneously administered RNAi therapeutic targeting ALN-AS1 in the development -- for the treatment of hepatic porphyrias including acute intermittent porphyria, or AIP. This trial will be conducted initially in AIP patients for asymptomatic high excreter or ASHE patients and then in AIP patients who experience recurrent porphyria attacks. We very much look forward to the continued advancement of ALN-AS1 including the start of our Phase I trial in the coming weeks with data expected in early 2016. We've also been actively enrolling AIP patients with recurrent porphyria into our EXPLORE Natural History study, where we're learning about the severity of porphyria effects and the enormous burden of disease for these patients. I'll now turn to review our progress from our cardiometabolic disease pipeline. Of course, our leading program in this study is ALN-PCSsc, which targets PCSK9 in development for the treatment of hypercholesterolemia. Our Phase I study continues in normal healthy volunteers with elevated baseline LDL, and we announced today that we've completed the single ascending dose portion of the study and have advanced to the multi-dose phase with or without statin co-administration. We expect to present initial clinical results from this Phase I trial in mid-2015. And pending abstract acceptance, we believe that we might present these data at the European Society of Cardiology Meeting being held August 29 through to September 2. Of course, we'll provide more specific details when they become available. Recall that the ALN-PCSsc program is partnered with The Medicines Company, which will lead full clinical development of the program from Phase II onwards and commercialization of the program thereafter if successful. Also in our Cardio-metabolic Disease STAr, we continue to advance a number of additional programs including our efforts on ALN-AC3, an investigational RNAi therapeutic targeting apoCIII. We're very excited about this program, which like PCSK9 targets an exquisitely well validated human disease target in cardiovascular disease. And finally, where there no clinical update at this time, we also make -- whilst there are no clinical updates at this time, we're also making strong progress in our Hepatic Infectious Disease STAr and on track to file our IND for ALN-HBV in late 2015. We continue to be very excited about ALN-HBV as we believe that it has the potential to emerge as the best-in-class RNAi therapeutic in the field, with subcutaneous dosing and a wide therapeutic window. Also, we are making progress on ALN-PDL, an investigational RNAi therapeutic targeting PD-L1. Here, a liver-specific inhibition of this immune checkpoint inhibitor could become a powerful approach to overcoming T-cell exhaustion associated with HBV infection without broad activation of immunity and untoward side effects thereof. In summary, we're making excellent progress on our RNAi therapeutics pipeline across all 3 STArs. It's certainly been an especially exciting and productive time for us, as we continue to lead the translation of the science of RNAi towards the development of innovative medicines. I will now turn the call over to Mike for a review of our financials. Mike?