Analyst; Telaprevir – the Mightiest in the Land

Off The Cuff

Thought this might be interesting, below is a bit of info from the investment site  istockanalyst........

Telaprevir – the Mightiest in the Land

Part two, click here for boceprevir part one.

Recall from yesterday, that SVR is what we consider a "cure rate."  So how did Telaprevir do in its trials?

Treatment naive patients – SVR cure rates of 79 percent compared with 46 percent in the standard of care group (Advance trial). 

Null responders – A 31 percent  SVR cure rate was found for null responders, compared with a 3percent SVR cure rate in patients who were retreated with the current standard of care, PEG-IFN + Rib (Realize Trial).  All treatments were administered for 48 weeks.  This is important because Boceprevir has not been given to null responders, which represents a sizable (~30%) treatment population.

Partial responders – a 61 percent SVR cure rate in the Telaprevir group versus a 15 percent cure rate found in the standard of care group.  All treatments were administered for 48 weeks.

Relapsers – an 84 percent SVR cure rate in the Telaprevir group versus a 22 percent cure rate found in the standard of care group.  All treatments were administered for 48 weeks.

Overall, very impressive results as compared with the current standard of care.

Additionally, two-thirds of patients are eligible to receive shortened 24-week treatment duration, in contrast to the current 48 week regimen.   This plays into a term called, response guided therapy (RGT), or doctor mediated control of dosing, where early response or decrease in HCV RNA is rewarded by early cessation of treatments.  Patients like this, as it means they do not have to experience a lot of the side effects concurrent with all three treatments - PEG-IFN, Rib or Telaprevir/Boceprevir.  Patients on RGT had SVR cure rates from 87 percent to -92 percent at 24 weeks of treatment (Illuminate trial).  Keep all of this in mind, as this is a strong positive for Vertex, as all other treatment types might have to live up to RGT's standards.

Here are some additional points to consider. Telaprevir, like Boceprevir, is a three times daily pill, although Vertex already has data showing that a two pill per day dose .   Also, in African-American populations, Telaprevir cured 62 percent  of patients versus 29 percent of patients in the standard of care control.   

What is clear from the data is that Vertex was better prepared and more elegant in their trial design than Merck.  They both have better efficacy and lots of data.  However, and this is a very important issue, both drugs have not been compared side by side.  Additionally, both drugs have different side effect profiles that might lead physicians to prescribe them differently.

Telaprevir – is this rash contagious and "Fire in the hole"?

In total, Telaprevir has been given to over 3,000 patients.  Of these patients, rash has been an issue with 56 percent of Telaprevir patients versus 34 percent of standard of care patients.  However, Vertex was aware of the issue and had in place a rash management plan that allowed doctor's to switch Telaprevir patients to standard of care therapy.  This kept the discontinuation rate in the trials low.

In over 90 percent of the patients, the rash was treatable with topical steroids.  However, there were three cases of Stevens Johnson Syndrome (SJS), a severe skin disease that recently claimed the life of former NBA star Manute Bol.  Fortunately, all the cases resolved.  Unfortunately, SJS is not something the FDA takes lightly and it has derailed drugs in the past.  Additionally, there were 11 cases of DRESS or drug rash with eosinophilia and systemic symptoms that mostly resolved, with one patient not returning for follow up.

So then, what is, "fire in the hole"?  Some patients complain of anorectal symptoms (29 percent for Telaprevir vs. 7 percent for standard care group). Vertex made clear that some patients experience a burning or itching at the onset of Telaprevir treatment.  However, symptoms resolve quickly and they did not record any patient discontinuations in their trials due to anorectal problems.

In conclusion, the FDA panel really spent time hammering away at the rash issue, but then concluded that Vertex had done a good job characterizing the problem and dealing with it.  Then they voted 18-0.  Overall, a lot of a drama for an expected result.

What about Vertex? Everything Sounds Great, Should I Buy?

Vertex (VRTX), closed today's trading at $55.05 per share.  Its current market cap is at $11.41 billion - not an insignificant amount for a company without a marketed product.  Net losses last year amounted to $754 million, with their only revenue coming from royalties and collaborations.  However, Vertex is a compelling company, even considered by many to be a Wall Street darling.   Both Telaprevir and its other phase-III drug, VX-770, are poised to achieve blockbuster status upon approval.  Now investors need to decide if the stock is overheated.  Perhaps this question is best answered by what type of sales and ultimate retained earnings deserves such a staggering valuation.  For this, investors need to decide for themselves what percent of the HCV market will be using Telaprevir versus Boceprevir.

In Case You Missed It....

Also, Over at the AIDS Beacon is a two part series on telaprevir and boceprevir;

This article is first in a two-part series that will discuss the benefits and drawbacks of two drugs, boceprevir and telaprevir, which are being developed for hepatitis C. Part 1 discusses the efficacy of the two drugs in clinical trials. Part 2 will discuss the complications and side effects for each 

Video Melissa Palmer, M.D. discusses in a two part series both new drugs Telaprevir & Boceprevir .