***Memo to the File***

NDA number:21-526 Elizabeth Hausner, D.V.M.

Sequence number/date/type of submission: N(000)B2 September29, 2003

Information to sponsor: Yes ( ) No (x)

Sponsor and/or agent: CVT Therapeutics

Manufacturer for drug substance :

Division name: Division of Cardio-Renal Drug Products

HFD #: 110

Drug:

Trade name: Ranexa

Generic name (list alphabetically): ranolazine

Code name: RS-43285-193, RS-43285-003, CVT-303, RAN D, Ran4

![](media/image1.png){width="3.4in" height="1.1222222222222222in"}
Chemical name:

CAS registry number: 95635-55-5

Mole file number:

Molecular formula/molecular weight: C~24~H~33~N~3~O~4~/427.54

![](media/image2.png){width="2.2333333333333334in" height="0.875in"}
Structure:

Relevant INDs/NDAs/DMFs: IND 43,735

Drug class: anti-anginal

Indication: angina

Route of administration: oral

Proposed use: angina for those patients in whom all other anti-anginals
are inadequate or not tolerated

The current submission was provided to try to address questions raised
in the Discipline Review Letter. The sponsor has submitted the
following:

Cerep 951003: In Vitro Pharmacology - Study of Several Compounds.
Binding of Ranolazine, Its

Enantiomers and Eleven Metabolites to the alpha1-adrenergic Receptors
and Opiate Receptors. Effects of Ranolazine, Its R- and S-enantiomers on
phenylephrine-induced Contraction in Isolated Rabbit Aorta.

Cerep 951006 and 951009: Binding of Ranolazine, Its Enantiomers and
Eleven Metabolites to

Human Serotonin 5-HT1A Receptors

CVT303.029-N: Binding of Ranolazine, Its Enantiomers and Three
Metabolites (CVT -2514,

CVT -2551 and CVT -3388) to the alpha-adrenergic Receptors in Rat
Tissues (Addendum to Cerep 951003)

CVT303.030-N: Binding of Ranolazine, Its Enantiomers and Eleven
Metabolites to the

beta-adrenergic Receptors and their Antagonism of Isoproterenol-induced
Increase in cAMP

CVT303.059-P: Electrophysiologic Effects of Ranolazine on Late ICa in
Isolated Canine Left

Ventricular Myocytes

CVT303.061-P: Ant arrhythmic Effects of Ranolazine in a Human LQT Model:
The In

Vitro Guinea Pig Heart Perfused with the Proarrhythmic Sea Anemone Toxin
ATX-II

CVT303.062-P: Functional Evidence of Anti-alpha Adrenergic Activity of
Ranolazine in Awake Rats

CVT303.063-P: Effects of Ranolazine Enantiomers on IKs, IKr, and Late
INa, and Ranolazine

Metabolites on Late Ina

CVT303.064-P: Functional Evidence of Anti-beta Adrenergic Activity of
Ranolazine in Awake Rats

CVT303.065-P: Effects of Ranolazine on Ventricular Repolarization in
Rabbit Isolated

Hearts

CVT303.066-P: Effect of Ranolazine, Its Rand S Enantiomers, and Eleven
Metabolites on Rat

Left Atrial Contractility

CVT303.067 -P: Effects of Ranolazine on Systemic Hemodynamics and
Coronary Circulation in

Conscious Dogs

CVT303.068-P: Electrophysiologic Effects of Ranolazine in
Arterially-perfused Wedge Preparations from the Canine Left Ventricle: A
Comparison Between Epicardial and Endocardial Stimulation

CVT303.069-P: Effect of Ranolazine on IKs in Isolated Canine Left
Ventricle Myocytes

CVT303.070-P: Effects of Ranolazine on Isoproterenol-, Forskolin-, and
Ouabain-induced

Delayed Afterdepolarizations and Triggered Activity of Guinea Pig
Ventricular Myocytes

MDS 1011172: Effect of the R- and the S-enantiomers of Ranolazine on the
Inhibition of

Neurogenic Twitch in Isolated Guinea Pig Ileum (a Serotonin 5-HT1A
Receptor-mediated Response)

MDS 1011220: Binding of Ranolazine, Its Enantiomers and Eleven
Metabolites to the Benzothiazepine, Dihydropyridine and
Phenylalkylamine-binding Sites of the L-type Calcium Channels

MDS 1033853: Effects of Ranolazine on Serotonin 5-HT1A, 5-HT2A and
5-HT2B Receptor-mediated Responses in Isolated Tissues

CVT303.013-R: Pharmacokinetics of Enantiomers of CVT -303 (Ranolazine),
CVT -3758 (S-Enantiomer), and CVT -3759 (R-Enantiomer) in Male Beagle
Dogs Following Intravenous Administration of CVT -303, CVT -3758 and
CVT-3759

CVT303.014-R: Pharmacokinetics of Enantiomers of CVT -303 (Ranolazine),
CVT -3758

(S-Enantiomer), and CVT -3759 (R-Enantiomer) in Male Sprague Dawley Rats
Following

Intravenous and Oral Administration of CVT -303, CVT -3758 and CVT -3759
CVT303.015-R: Pharmacokinetics of Enantiomers of CVT -303 (Ranolazine),
CVT -3758 (S-Enantiomer), and CVT -3759 (R-Enantiomer), in Male Beagle
Dogs Following Oral Administration of CVT -303, CVT -3758 and

CVT -3759

Attachment 5-1: Assessing Predictors of Drug-induced Torsade de Pointes

Attachment 5-2: Ophthalmology Data

Attachment 5-3: Pathology Data

Attachment 5-4: Summary of Results. Organ Weights and Microscopic
Findings for Male and Female

Reproductive Organs in Individual Repeated Dose Oral Studies in Rats and
Dogs

**This memo is not so much a review as a statement and brief commentary
on the material provided.**

*Cerep 951003 Binding of ranolazine, its enantiomers and eleven
metabolites to the α1-adrenergic receptors and opiate receptors. Sept
10, 2003*: Ranolazine and the R and S enantiomers showed \< 20%
inhibition of specific 3H-naloxone binding to opiate receptors in
membranes prepared from rat cerebral cortex. Two of the metabolites
(CVT-3388 and CVT5030) showed significant binding to the opiate
receptors with Ki values of 2.7 and 2.3 μM respectively. Both of these
metabolites produced 68% inhibition of specific tritiated naloxone
binding. Ranolazine, both enantiomers and several metabolites showed
significant α-adrenergic receptor binding as summarized in the
reviewer's table below.

Ki values (μM) of test compounds for α-adrenergic and opiate receptors
in rat cerebral cortex

  ----------------------- ----------------------- -----------------------
                          α-adrenergic receptors  Opiate receptors

  Ranolazine              1.9                     n.d.

  R-enantiomer            2.1                     n.d.

  S-enantiomer            1.7                     n.d.

  CVT-2514                4.9                     n.d.

  CVT-2551                2.6                     n.d.

  CVT-3388                1.5                     2.7

  CVT-5030                \>30                    2.3
  ----------------------- ----------------------- -----------------------

n.d.= not done

Ranolazine and both enantiomers were also effective in the
phenylephrine-induced contraction in rabbit aorta, supporting
α-adrenergic ability.

*Cerep 951006 and 951009 Summary: Binding of ranolazine, its enantiomers
and eleven metabolites to human serotonin 5-HT~1A~ receptors.* *Sept 10,
2003*

The report lists Ki values for ranolazine and its enantiomers for opiate
receptors as well as 5HT~1A~ binding. These are summarized in the
reviewer's table below.

  ----------------------- ----------------------- -----------------------
                          Ki value (μM) for       %inhibition of specific
                          opiate receptors        binding (10μM)human
                                                  serotonin 5HT1A in
                                                  mammalian cells (Ki μM)

  Ranolazine              2.1                     71

  R-enantiomer            13.0                    32

  S-enantiomer            1.0                     81

  CVT-3248                                        6

  CVT-2537                                        13

  CVT-3388                                        52

  CVT-2551                                        80

  CVT-2514                                        64

  CVT-2513                                        27

  CVT-2512                                        13

  CVT-2738                                        20

  CVT-2535                                        -10

  CVT-4786                                        12

  CVT-5030                                        39
  ----------------------- ----------------------- -----------------------

CVT303.029-N : Addendum to Cerep 951003, Binding of ranolazine, its
enantiomers and 3 metabolites to α-adrenergic receptors. The study
confirmed the previous findings that ranolazine and several of the
metabolites showed α-adrenergic binding. The sponsor's table is shown
below.

![](media/image3.png){width="4.434027777777778in"
height="1.7118055555555556in"}

![](media/image4.png){width="4.058333333333334in"
height="1.9243055555555555in"}

*Electrophysiology studies:*

The electrophysiology findings provided do not supersede the clinical
findings of QT prolongation and cannot be extrapolated to provide human
safety information

*CVT303.064-P Functional evidence of anti-beta adrenergic activity of
ranolazine in awake rats. July-August 2003.* The study provides evidence
that ranolazine has functional β-adrenergic antagonistic activity in
conscious rats. Atenolol was used as a comparator compound in attempts
to modify the dose-response curve of isoproterenol. A less specific
β-blocker such as carvedilol might have been a more appropriate
comparator. The sponsor does not show time course data for the
cardiovascular effects

*CVT303.067-P Effects of ranolazine on systemic hemodynamics and
coronary circulation in conscious dogs. August 11, 2003-September 5,
2003.* Chronically instrumented dogs were given increasing intravenous
doses of ranolazine with a 30 minute interruption of infusion between
each dose ( bolus + infusion). The experimental protocol for each dose
lasted 45 minutes with recordings of the measured parameters obtained at
0, 5,10, 15, 20, 30 and 45 minutes and blood samples collected after
each recording except for 0 minutes. However, the only data presented or
discussed was the 0 and 15 minute data. This "snapshot" view of the
results is unhelpful and unacceptable. As reported, the study is
inconclusive.

*MDS 1011172 Effect of the R- and S- enantiomers of ranolazine on the
inhibition of neurogenic twitch in isolated guinea pig ileum (a
serotonin 5-HT~1A~ receptor-mediated response). August 28, 2003*
Apparently significant agonism was seen as demonstrated by a ≥ 50%
decrease in field stimulated contractile responses by CVT3758
(S-enantiomer, 68% agonism at 10 μM)and CVT-3759(R-enantiomer, 157%
agonism at 10 μM) at concentrations of ≥10μM. A selective serotonin
5HT~1A~ antagonist WAY-100635 produced minimal reversal of the
enantiomers effects. Was there a problem in the assay or are the effects
due to factors other than serotonin antagonism? A dose response was
shown in the results.

*MDS1033853 Effects of ranolazine on serotonin 5-HT~1A~, 5-HT~2A~ and
5-HT~2B~ receptor-mediated responses in isolated tissues.* Ranolazine
inhibited the neurogenic twitch in isolated guinea pig ileum (a
serotonin 5-HT~1A~ receptor mediated response) with an EC~50~ value of
5.3μM. No activity was reported for 5HT~2A~ and 5HT~2B~ receptors as
measured by contraction or inhibition of agonist-induced contraction in
rat aorta or stomach respectively.

*MDS 1011220 Binding of ranolazine, its enantiomers and eleven
metabolites to the benzothiazepine, dihydropyridine and phenylalkylamine
binding sites of the L-type calcium channels. August 14, 2003* Very
minimal calcium channel binding was demonstrated.

*CVT303.013-R Pharmacokinetics of enantiomers of CVT-303(ranolazine),
CVT-3758(S-enantiomer) and CVT-3759(R-enantiomer) in male Beagle dogs
following intravenous administration of CVT-303, CVT-3758 and CVT-3759.
June 4- June17, 2003*

Three male dogs were used in this pharmacokinetic comparison of the
enantiomers when given in the racemic mix and when given individually.
The plasma analysis procedure used produced baseline resolution of the
enantiomers with retention times of 9.6 (CVT-3758) and 15.5 (CVT-3759)
minutes. The sponsor's results are shown below.

![](media/image5.png){width="6.498611111111111in"
height="2.2305555555555556in"}

There appear to be slight differences in the AUC and clearance values
for the enantiomers where the S enantiomers appears in the plasma at a
ratio of 1.1 to 1.7 compared to the R- enantiomers. The clearance for
the R-enantiomer is slightly higher than that for the S-enantiomer. AUC
for the S-enantiomer was also slightly greater than AUC for the
R-enantiomer. While the results are consistent between the
administration of the racemic mix and the single isomers, the sample
size is small. Also, it was reported that both compounds were below the
limits of detection by 1(R-enantiomer) to 2(S-enantiomer) hours after
intravenous dosing. Therefore, the sampling times of 2,5,15 and 30
minutes followed by 1,2,4,6,8,10 12 and 24 hours post-dose were not
optimal for characterization. The report noted that the R enantiomer was
not found after intravenous dosing of the S-enantiomer and vice versa.

*CVT303.014R Pharmacokinetics of enantiomers of CVT-303, CVT-3758 and
CVT-3759 in male Sprague-Dawley rats following intravenous and oral
administration of CVT303, CVT3758 and CVT3759. August7-18, 2003.* Oral
and intravenous doses of the racemic mix and the enantiomers were
tested. Quantification was by the same chiral separation methods as used
for the dog study.

Blood samples were collected from the rats at 2.5, 5, 15.30 minutes and
1, 2, 4, 6, 8 and 24 hours after intravenous dosing and at 5, 15, 30
minutes and 1, 1.5, 2, 4, 6, 8 and 24 hours after oral dosing.

The sponsor's results are shown below.

![](media/image6.png){width="4.807638888888889in"
height="3.3201388888888888in"}

![](media/image7.png){width="4.179166666666666in"
height="2.290277777777778in"}

At each dose by both routes of administration, the S-enantiomer produced
non-significantly higher plasma levels than did the R-enantiomer.
Clearance was also slightly higher for the R-enantiomer. Bioavailability
was slightly greater for the S-enantiomer. The results are consistent
with the dog study. The report noted that the R enantiomer was not found
after either oral or intravenous dosing of the S-enantiomer and vice
versa.

*CVT303.015-R Pharmacokinetics of enantiomers of CVT-303, CVT-3758 and
CVT-3759 in male Beagle dogs following oral administration of CVT-303,
CVT3758 and CVT3759. August 11- August 27, 2003.* Four male Beagles
received oral doses of either the racemic mixture or the enantiomers of
ranolazine. Blood samples were collected at 2,5, 15, and 30 minutes and
at 1,2,4,6,8,10, 12 and 24 hours post-dose. The results from this study
were consistent with the previous two studies. The report noted that
CVT-3759 was not found in plasma after administration of CVT-3758 and
vice versa.

*Assessing predictors of drug-induced torsade de pointes. Accepted in
Trends in Pharmacological Sciences. Noted as scheduled for publication
in December 2003.*

This is a preprint of a manuscript authored by the sponsor the details
the sponsor's criteria for deciding pro-arrhythmic risk from preclinical
studies.

Attachment 5-2: In a telecom, this reviewer expressed a concern that
none of the preclinical toxicology reports included an ophthalmologist's
report, nor any indication that a board certified veterinary
ophthalmologist had examined any of the animals in any studies. In fact,
there are recent studies where it was specified that examinations were
conducted by a staff veterinarian instead of an ophthalmologist. In
response to that concern, the sponsor has sent the individual animal
data for the ophthalmic exams for the following studies:

AT3465: RS-43285RHT: Three month oral toxicity study in rats

AT3935: RS43285 RJT: Six month oral toxicity study in rats with one
month recovery period.

AT6544: RS-43285-RKT: One year rat toxicity study

AT3440: RS-43285DHT: Three month oral toxicity study in dogs

AT4050: RS-43285DJC:six month oral toxicity study in dogs

AT6971: RS-43285 DKC: One year oral toxicity study in dogs

While the individual animal sheets are signed, there is no indication
that the person signing is a qualified veterinary ophthalmologist. There
is no summary of the findings, and no statement from the person
conducting the examinations as to a conclusion.

Attachment 5.3 Pathology data

In the above mentioned telecom, this reviewer also noted that there was
no complete summary of histopathologic findings provided for any study
and that the absence of data did not mean that one could assume that
there was no problem. In this attachment, the sponsor has provided
material for the following studies:

AT3465: RS-43285RHT: Three month oral toxicity study in rats

AT3935: RS43285 RJT: Six month oral toxicity study in rats with one
month recovery period.

AT6544: RS-43285-RKT: One year rat toxicity study

AT3440: RS-43285DHT: Three month oral toxicity study in dogs

AT4050: RS-43285DJC:six month oral toxicity study in dogs

AT6971: RS-43285 DKC: One year oral toxicity study in dogs

The material submitted does not significantly contribute to elucidation
of the histopathological questions.

Summary: The material submitted does not materially change the
preclinical characterization of ranolazine.