Vertex Cystic Fibrosis Program

Vertex Pharmaceuticals (VRTX) has been, and will continue to be the leader in therapy for people with Cystic Fibrosis. Below is an update of all the different drugs in clinical trials that the company is currently running, including deuterated ivacaftor (VX-561), formerly known as CTP-656 that was purchased for $160 million from Concert Pharmaceuticals in July. Concert is eligible for up to $90 million more, dependent upon how far VX-561 progresses.

Twice Daily  
Ivacaftor 
Ivacaftor + Lumacaftor
Ivacaftor + Tezacaftor

Twice Daily Triple Combo Phase 2
Ivacaftor + Tezacaftor + VX-440 
Ivacaftor + Tezacaftor + VX-152
Ivacaftor + Tezacaftor + VX-659
Ivacaftor + Tezacaftor + VX-445

Once Daily Triple Combo Phase 2
VX-561 + Tezacaftor + VX-659 readout March 2018
VX-561 + Tezacaftor + VX-445 readout April 2018

The Ivacaftor patent runs to 2027, the Deuterated Ivacaftor (VX-561) patent runs into 2031. The goal for the program is to create a triple combo (1 potentiator, 2 correctors) once daily dosing for the majority of CF people with the F508del mutation. The company plans to run phase 3 triple combo trials in 2018.  Thank you for reading.

GLPG2451 for Cystic Fibrosis

Galapagos is aggressively pursuing drugs for people living with cystic fibrosis.  We previously wrote about Galapagos extensively here Galapagos.  Their previous top candidate, potentiator GLPG1837, has now been put on hold for a much more convenient once daily dosed potentiator GLPG2451.  The drug has completed the safety phase 1 clinical trial in healthy subjects, and by Galapagos standards was viewed as ready for a phase 1 combo trial with their lead corrector GLPG2222.  The ultimate goal for the company is to develop a triple combination for people with the F508del mutation, which represents around 90% of the total CF population.  The phase 1 and 2 clinical trials are being funded almost 100% by their partner AbbVie.  If this phase 1 combo clinical trial passes the safety test, then a third component corrector GLPG2737, which is currently in the safety phase of testing, will then be added to the combo 2451 and 2222 to form the triple.  The big picture goal is to produce a better therapy than currently approved Vertex's two drug combo Orkambi.  A once daily triple combo would be advantageous for CF patients that may take up to 20-40 pills per day for this disease. 

Interim Analysis of 2451 and 2222
According to Galapagos, an interim analysis will be conducted on the combo mid-year.  If the combo passes the safety test, then corrector #2 GLPG2737 will then be added to the mix, and the three drugs will be tested for CF patients with F508del around third quarter of 2017.  So, by the end of 2017, the first triple combination (one potentiator, and two correctors) will be tested.  However, if the current phase 1 clinical trial with 2451 and 2222, does not produce an acceptable drug/drug interaction safety profile in healthy participants, then the entire project would be delayed.   

CTP-656  in Phase 2
Concert Pharmaceuticals CTP-656 is currently in a phase 2 clinical trial as mono-therapy for CF patients harboring the G551D mutation.  The drug is dosed once daily, and has shown head to head comparison's with Kalydeco in several early clinical trials with PK advantage.  The drug could fit nicely into the mix for a combo also, with two correctors, dosed as one simplified daily pill for F508del CF patients. 

Bottom Line: 
We'll monitor progress of the Galapagos combo clinical trial (2451 + 2222), and CTP656's phase 2 clinical trial that is scheduled to complete by the end of 2017.  Thank you for reading. 

CTP-656 For Cystic Fibrosis

CTP-656 is the name of Concert Pharmaceuticals deuterated version of Vertex's Kalydeco, which is approved for cystic fibrosis patients with the G551D mutation, and as combo with corrector Lumacaftor (known as Orkambi), for patients with the F508del mutation.  The hope is that CTP-656 enhances therapy for cystic fibrosis patients by improving the metabolic profile, reduce dosage to once daily, or ameliorate drug interaction, over currently FDA approved Kalydeco.  Thank you for reading.
 

VX-661 Corrector for Cystic Fibrosis

Vertex is currently involved with four phase 3 cystic fibrosis clinical trials for people with the F508del mutation, and the combination of potentiator Ivacaftor + corrector VX-661.  Today they gave an update regarding one of the four phase 3 clinical trials that are in progress.  The complete press release is here Vertex Provides Update on Ongoing Phase 3 Program for VX-661 in Combination with Ivacaftor for the Treatment of Cystic Fibrosis. 

                 

N91115 CFTR Stabilizer

Nivalis Therapeutics (NVLS) is a clinical stage company that specializes in treatments for Cystic Fibrosis, with it's lead candidate stabilizer N91115.  N91115 is the only clinical stage candidate designed to stabilize CFTR (Cystic Fibrosis Transmembrane Conductance) inside the cell and at the cell surface.  The company expects N91115 to be complimentary to existing and future CFTR modulators, and is currently in a phase 2 clinical trial with approved drug Orkambi for people with the F508del mutation.  The trial is designed to see what effect N91115 may have as addition to what Orkambi achieves.  Below is the clinical trial and efficacy goals the company expects from this trial.

- N91115 in Patients With CF Homozygous for the F508del-CFTR Mutation.
- The company is targeting a 5% improvement, up and over Orkambi's 3% range in ppFEV1.
- Readout of data will be 2nd half 2016.
- First readout for a triple with three distinct therapies, for F508del homozygous patients.
- Have received Orphan and Fast Track designations from FDA in 2016.
- The patent for N91115 runs until 2031 at the very earliest.

The company plans to couple N91115 with leading potentiator's to potentially increase efficacy for combo therapy.  Either Kalydeco, CTP-656 or GLPG1837 are the current group of potentiator's that hold the most promise to date.  Thank you for reading.

CTP-656 Cystic Fibrosis Market Opportunity

CTP-656 is the deutered version of Vertex drug Kalydeco.  Today, Vertex gave an updated sales forecast for Kalydeco at the JP Morgan Healthcare Conference.  The company expects 2016 revenues in the range of $675 million.  Kalydeco is provided to Cystic Fibrosis patients as mono therapy for the G551D and R117H mutation.  The annual cost of the therapy is approximately $300,000 annually.
Concert Pharmaceuticals plans on seeking regulatory approval for CTP-656 as mono therapy for people with the G551D and other gating mutations.  What could peak revenue look like for this set of patients excluding the more common F508del.  Below is the worldwide patient population for Kalydeco as mono-therapy, excluding any combination therapies for the most common form of CF, the F508del mutation, for which Orkambi is prescribed for.

• G551D ages 6+ (US) 
• G551D ages 6+ (EU, AUS & CAN)  
• Gating, R117H & Ages 2-5
• 4,000 eligible patients (Vertex Pharmaceuticals 2015 Year End Presentation)

The unique situation Concert finds itself in, if CTP-656 potentially does get FDA approval as mono-therapy, is that the footprint for those 4,000 patients available, have already been established from being prescribed Kalydeco.  The switch to CTP-656 from Kalydeco, could happen seamlessly if the drug is marketed right.
 

Penetration rate of 70% = 2,800 patients
Annual therapy price of $240,000 (20% discounted)
Potential revenue 2,800 patients * $240,000 annual therapy = $672 million

The advantages that CTP-656 offers is a once daily, with less dietary restrictions, that should lead to higher adherence rates. Thank you for reading.

 

Is Adherence to Ivacaftor Suboptimal

From a recent issue of the Journal of Cystic Fibrosis, the authors make a strong case that twice daily Ivacaftor adherence is suboptimal.  Although used interchangeably, let's attempt to differentiate between compliance and adherence. If a doctor prescribes Ivacaftor 150 mg twice daily, and you accept and fill the prescription, you are in compliance with your doctor. Taking Ivacaftor twice daily is adherence to the prescription requirements.  The link to the article is below.  
Adherence_to_Ivacaftor_is_suboptimal
In the small sample study, the authors found that adherence was 61% among patients prescribed Ivacaftor.  Keep in mind they studied patients taking Ivacftor for the G551D mutation, which showed an improvement of over 10% percentage points in clinical trials, in the percent predicted FEV1.  The latest  FDA approved combo Orkambi (Ivacaftor and Lumacaftor) scored much lower on FEV1 for patients with F508del, than what Ivacaftor alone did for G551D patients. There are a few companies currently working on a once daily for CF patients, which could increase adherence rates to a higher level. Thank you for reading.

Orkambi Gets FDA Approval

Today the FDA approved the combination of Vertex's Lumacaftor and Kalydeco (Orkambi) for cystic fibrosis people, 12 years and older, with two copies (homozygous) of the F508del mutation. We originally wrote about Orkambi here Vertex Pharmaceutical Passes Advisory Committee, when they were front and center with the FDA advisory committee.

Orkambi has been appoved for CF patients despite the relatively small improvement in FEV1 in two F508del clinical studies.  How high is the bar set for other companies to get clinically significant improvement over Kalydeco as mono therapy for the G551D mutation, and Orkambi combination therapy, for patients 12 years and older, with two copies of the F508del mutation?

G551D Through 24 weeks Kalydeco 150 mg q12h

• 10.6% and 12.5% FEV1 improvement vs. placebo

G551D Through 48 weeks Kalydeco 150 mg q12h

• 10.5% and 10.0% FEV1 improvement vs. placebo
• 3,000 Worldwide Patients

F508del Through 24 weeks 2 tablets (ivacaftor 125 mg / lumacaftor 200 mg) q12h

• 2.6% and 3.0% FEV1 improvement vs. placebo
• 26,000 U.S. + EU Orkambi Patient Potential

These are the FEV1 (forced expired volume) numbers that other companies will be considering as significant, to improve current therapy for CF patients.  The side effect profile was mild, as a high percentage of patients completed the Vertex clinical trials.  The annual wholesale acquisition cost (WAC) will be priced at around $259,000 per patient for the Orkambi combination.  Thank you for reading.