Welcome to the Voyager Therapeutics Fourth Quarter and Full Year 2015 Financial and Operating Results Conference Call. [Operator Instructions]. At this time I would like to turn the call over to Sarah McCabe of Stern Investor Relations. Please proceed.

Thank you, Operator. Good morning this is Sarah McCabe with Stern Investor Relations and welcome to the Voyager Therapeutic fourth quarter and full year 2015 financial and operating results conference call. This morning we issued a press release which outlined these results and provides the business update that we plan to discuss today. The releases available at www.voyagertherapeutics.com. Today in our call, Steve Paul, President and CEO will discuss the business and clinical highlights. Jeff Goater, CFO will review the financial results and then we will open up the call for your question. Bernard Ravina, VP of Clinical Development is also on the call and will be a valuable for Q&A. Before we begin just a reminder that the estimates and other forward-looking statements included in this call represents the company's view as of today March 17, 2016. Voyager disclaims any obligation to update these statements to reflect future events or circumstances. Please refer to today's earnings really as well as Voyager's filing with the SEC for information concerning risk factors that could cause actual results to differ materially from those expressed or implied by such statements. With that let me pass the call over to the Steve.

Thank you, Sarah and good morning everyone. 2015 was certainly a momentous year here at Voyager. In February we entered into a transformative strategic collaboration with Sanofi Genzyme. In April we closed our Series B financing and in November we completed a successful IPO all the while continuing to make significant progress advancing our pipeline of novel AAV gene therapies for severe CNS diseases. I just want to take a moment to thank all of our Voyager employees, our Board members, advisors and consultants for their extraordinary efforts and hard work that has placed us in an excellent operational and financial position moving forward. Since the founding of Voyager we have assembled an outstanding R&D team that has pioneered significant advances in AAV gene therapy, neuroscience, CNS drug discovery and it importantly has extensive drug development expertise. The CNS is an attractive therapeutic area for AAV gene therapy for a number of key reasons. Durable gene expression is achievable in the CNS due to the fact that the target cells or neurons are no longer dividing. In our Parkinson's program for example we have data showing sustained therapeutic gene expression, out four years in patients and over eight years in preclinical studies. Targeted delivery to specific regions of the brain and broader delivery to the spinal cord is achievable using AAV and this has been shown in both preclinical and clinical studies. There are many CNS diseases that are monogenic or caused by a single gene. So the biological target and thus therapeutic strategy we're pursuing is highly validated. Because the CNS is a relatively contained or enclosed space due to the blood brain barrier, it is immune privileged thus the likelihood of a significant immune response following vector administration is relatively low and the challenge of preexisting immunity to…

Thank you, Steve. As Steve mentioned, we're in a strong financial position as a result of the Sanofi Genzyme collaboration, our series B financing and our successful IPO, all completed in 2015. In this morning's press release, we reported cash, cash equivalents and marketable securities totaling approximately $224 million as of December 31, 2015, compared to approximately $161 million as of September 30, 2015. The total includes net proceeds of approximately $73 million from our IPO in November of 2015. Our GAAP net loss for the fourth quarter of 2015 was $8.8 million or $0.67 per share, compared to a net loss of $5.2 million or $6.58 per share, for the same period in 2014. Our GAAP net loss was $38.3 million or $9.14 per share, for the year ended December 31, 2015, compared to a net loss of $17.7 million or $27.83 per share, for the same period in 2014. Our R&D expenses for the fourth quarter of 2015 were approximately $9.2 million compared to $3 million for the same period in 2014. The increase was largely due to expenditures in advancing development of our pipeline and product engine, including increased R&D personnel costs associated with the growth of the Company. Our R&D expenses were $27.7 million for the year ended December 31, 2015 compared to $8.9 million for the same period in 2014. Our G&A expenses were $3.2 million for the fourth quarter of 2015, compared to $1.5 million for the same period in 2014. The increase was largely due to expenditures in G&A personnel associated with the growth of the Company, including expenses related to operating as a public company. G&A expenses were $9.9 million for the year ended December 31, 2015 compared to $5.5 million for the same period in 2014. To support our continued growth…

[Operator Instructions]. Our first question comes from Josh Schimmer with Piper Jaffray. Your line is open.

I have 2.5 questions. First, can you describe the learning curve at the Pittsburgh site in terms of the procedure and their ability to adopt it seamlessly?

So, the Pittsburgh site is actually very experienced doing clear point for deep brain stimulation. So that's why we selected them as a site. The neurosurgeon there, Mark Richardson, also has quite a bit of experience doing infusions for other indications such as brain tumors, so they are really very well prepared to participate in this study. So, the learning curve is -- they really doing extremely well.

Yes. And Josh, let me add that the teams have sort of cross-trained, so they visit each other in the OR at each institution. For example, at UCSF, on the last patient, the team from Pittsburgh was there and the team from UCSF will travel to Pittsburgh and will be participating in the initial surgeries there as well. So, there's a very, very close connection between those two teams.

How do you then think about scaling it up into a broader group of centers for Phase III and then commercialization?

And again, as we indicated earlier we're using a clear point system as a commercial system. That's available at some 20-plus academic medical centers. We plan to then identify and we've already started that process, a number of other surgical sites or medical centers that can do this procedure and scale up from there. Conceivably, we will begin initiating studies at other sites in the very near future.

And then for the ongoing trial, are you screening patients for baseline immunogenicity to AAV2? In your prepared remarks, it sounded like not necessarily. And also are you looking at baseline PET imaging to confirm some threshold level of AADC activity? And if so, how are you finding kind of the baseline screen or success rate for diminished activity?

We think the problem of pre-existing immunity for intra-cerebral administrations we're doing is going to be very, very markedly reduced. As you know, antibodies in the systemic circulation get into the brain only at about 0.1% mass-to-mass volume. And therefore, we don't think this is going to be a problem moving forward. Having said that, we're routinely screening patients now, in the event we find someone with a high titer of antibody against AAV2, we will eliminate them, exclude them from the study because recently don't want that to be a confounding factor. It doesn't seem to have been much of a problem to date. I think there's only been one patient that had high enough antibodies to make us want to select another patient for the trial. So, moving forward, we don't think this is going to be a problem. I forgot your next question Josh, did you have another one?

Yes, baseline AADC imaging.

Yes. Actually, of course we do get the PET scan at baseline, but the patients are really enrolled on the basis of the severity of their motor symptoms to begin with, the response, the early response the patient had to levodopa. We don't really use AADC PET as a way of screening patients. It's uniformly dramatically reduced in these patients just to begin with. This is a very, very common finding. So we don't use the PET for that purpose. We do want to obviously use the PET to make sure that we've delivered enough of the gene. And as I underscored, in this case, we can actually measure the gene product itself, the enzyme, the catalytic activity of that enzyme with the PET tracer fluorodopa. So it's really quite a unique opportunity to help us know how much we've actually given back, if you will or delivered back to the patient.

Our next question comes from Jeff Chen with Cowen & Company. Your line is open.

The first one is on the decision in terms of the need to increase dosing if necessary. Is that decision going to be made midyear when you announce the putamen coverage or is that more toward Q4 data disclosure?

This is a dose ranging study. Our goal is of course to both assure that we're safe, that the procedure is safe and then also to optimize the dose. It is our current thinking that we will get additional data. And the three-month data as we reported for patient number six, for patients number seven, eight, nine and 10 should be informative and that will help us determine whether or not we should increase the dose further. We can go up with the current formulated product, up on the dose about sixfold. We could also potentially increase the volume of it. The volume looks pretty good right now with respect to the coverage we've obtained. Particularly we've seen good coverage in patient number eight which we've reported already. So I think we're just going to have to take it patient by patient, but in aggregate, we would love to see the results for the second five patients at three months to determine whether we need to dose escalate even further.

And so then the data at the -- in Q4, in terms of prioritization of what's most important in all of these biomarkers and this was off-time in UPDRS scores, could you help us understand which ones that you would emphasize on in terms of clinical benefit?

I think they're all pretty importantly -- they tell us different things. So the PET scans will tell us how much of the gene we've delivered and to what extent does that expressing active protein active enzyme and that's pretty important to us. And we will have reference standards there with patients that don't have Parkinson's disease, etc. So we will get some really good idea of how much we've delivered. The levodopa challenge test is a relatively objective way of looking pre- and post-surgery at the responsiveness of the patient to levodopa, so I like that test a lot in terms of what it might tell us. And most importantly obviously though -- are we achieving a clinically meaningful response of the patient post-surgery versus pre-surgery on his or her off-time and on-time and UPDRS measurements. Obviously, we like to do that without any troublesome dyskinesia. So I think all of them are important. For me, the clinical endpoints trump, but showing that the biomarkers --since this is a non-controlled or a non-sham controlled trial, are all going in the right direction are also important.

Our next question comes from David Nierengarten with Wedbush. Your line is open.

Maybe stepping aside from Parkinson's for a second, I was just wondering if there have been or how you have been watching the competitive landscape evolve in CNS gene therapy and if that has changed or affected your prioritization for your next IND. Thanks.

Not really. We do watch and monitor the competitive landscape quite closely. We think we're in a very competitive position right now with all of our programs and so they are advancing as at rapid rate as we can advance them and again, we think the likelihood is that the next IND will be in ALS or Friedrich's program or both, around the same time, hopefully towards the end of next year.

I'm showing no further questions. I will now turn the call back over to Steve Paul for closing remarks.

In closing, we just want to thank everyone for their interest and in their support of Voyager Therapeutics. We're extremely excited about the transformative potential of AAV gene therapy and we're highly motivated to develop these novel therapies for patients with these severe CNS diseases. 2015 was clearly a transformative year for the Company and we're looking forward to an even better 2016. Thanks again for your time and we look forward to updating you on our progress again very soon. Thank you.

Thank you. Ladies and gentlemen, that does conclude today's conference. You may all disconnect and everyone have a great day.