Development and Validation for Simultaneous Estimation of Etoricoxib and Pregabalin in Bulk and Tablet Dosage Form by RP-HPLC 2K20,GTU,MASTER IN PHARMACY IN QA

1. GUIDED BY
DHIRENDRA KUMAR TARAI
PREPARED BY:
UPEKSHA J. BAVADIYA
Department of Pharmaceutical Quality Assurance
GUJARAT TECHNOLOGICAL UNIVERSITY
Chandkheda, Ahmadabad – 382424 - Gujarat
“A REVIEW ON ETORICOXIB AND
PREGABALIN IN METHOD VALIDATION BY
RP-HPLC”

2. 1. INTRODUCTION (1-8)
2

3. INTRODUCTION OF DRUG (ETORICOXIB)(1)
3
 Etoricoxib, sold under the trade name Arcoxia, is a selective COX-2
inhibitor from McOLSON Research Laboratories. Currently it is
approved in more than 80 countries worldwide but not in the US, where
the Food and Drug Administration (FDA) has required additional safety
and efficacy data for Etoricoxib before it will issue approval
 Etoricoxib is indicated for the treatment of rheumatoid arthritis,
psoriatic arthritis, osteoarthritis, ankylosing spondylitis, chronic low
back pain, acute pain, and gout. Approved indications differ by country.
In the U.K., it is also "used for the short term treatment of moderate
pain after dental surgery" of adults.
 MOA : Like any other COX-2 selective inhibitor Etoricoxib selectively
inhibits isoform 2 of cyclo-oxigenase enzyme (COX-2), preventing
production of prostaglandins (PGs) from arachidonic acid.

4. INTRODUCTION OF DRUG (PREGABALIN)(2)
 Marketed under the brand name Lyrica among others, is a medication used to
treat epilepsy, neuropathic pain, fibromyalgia, restless leg syndrome, and
generalized anxiety disorder Its use in epilepsy is as an add-on therapy for
partial seizures. When used before surgery, it reduces pain but results in
greater sedation and visual disturbances It is taken by mouth
 Common side effects include headache, dizziness, sleepiness, confusion,
trouble with memory, poor coordination, dry mouth, problem with vision,
and weight gain. Serious side effects may include angioedema, drug misuse,
and an increased suicide risk.
 MOA : Act as a ligand of the alpha2-delta subunit of calcium channels.
Decreased calcium entry into nerve endings. less glutamate released from
nerve endings .than relief of neuropathic pain.
4

5. Introduction to Dosage form
Brand Name Contents Manufacturer Formulation
Etoshine NP
Etoricoxib
+
Pregabalin
Sun Pharma
laboratory pvt. Ltd
Tablet
5

6. TECHNIQUES OF METHOD DEVLOPMENT
6

7. INTRODUCTION OF ANALYTICAL METHOD (3)
 Analytical chemistry is divided into two branches:
 Qualitative: A qualitative analysis provides information about the identity of
atomic or molecular species or functional groups in sample.
 Quantitative: A quantitative analysis provides numerical information as to the
relative amount of one or more of these components.
 Analytical methods development and validation play important roles in the
discovery, development and manufacture of pharmaceuticals with the objectives. To
qualify and quantify the active pharmaceutical ingredients in bulk as well as
dosage form To establish impurity profile and limit of allowable impurities in
dosage form.
7

8. 8
INTRODUCTION OF HPLC METHOD (4)
 HPLC is an analytical technique widely used for identification, separation, detection
and quantification of various drugs and its related degradents.
 High performance liquid chromatography (HPLC), is a separation technique based
on a solid stationary phase and a liquid mobile phase. Most of the drugs in multi-
component dosage forms can be analyzed by HPLC method because of the several
advantages like rapidity, specificity, accuracy, precision and ease of automation in
this method. HPLC method eliminates tedious extraction and isolation procedures.
 Principle of separation:
 The principle of separation in normal phase mode and reverse phase mode is
adsorption. When mixtures of components are introduced in to a HPLC column,
they travel according to their relative affinities towards the stationary phase. The
component which has more affinity towards the adsorbent travels slower. The
component which has less affinity towards the stationary phase travels faster. Since
no two components have the same affinity towards the stationary phase, the
components are separated.

9. CONT…..
 Different modes of separation in HPLC:
1) Normal phase mode.
2) Reverse phase ion pair chromatography.
3) Reversed phase mode.
4) Size exclusion chromatography.
9

10. Method development by RP-HPLC (5)
10
 Reversed-phase chromatography is the mainly used in chromatographic
mode, it is used to separate neutral molecules in solution based on their
hydrophobicity.
 As the name suggested that, reversed-phase chromatography is the
reverse of normal-phase chromatography in the intelligence that it involves
the employ of a polar mobile phase and a non-polar stationary phase.
 It ensures that a decrease in the polarity of the mobile phase results in a
decreases in solute retention.

11. 11
HPLC Techniques
Normal phase
Mode
Stationary phase : Polar
Mobile phase : Non polar
Reverse phase Mode
Stationary phase : Non
polar
Mobile phase : Polar

12. 12
Fig. A schematic diagram of HPLC equipment.

13. VALIDATION OF ANALYTICAL METHOD (14)
13
Validation
Validation is a process of establishing documented evidence, which provides a high
degree of assurance that a specific activity will consistently produce a desired result
or product meeting its predetermined specifications and quality characteristics.
Method Validation
Method validation is the process used to confirm that the analytical procedure
employed for a specific test is suitable for its intended use.
Results from method validation can be used to judge the quality, reliability and
consistency of analytical results.

14. Validation of Analytical method
14

15. 2. DRUG PROFILE (15-17)
15

16. 2. Drug profile of Etoricoxib (17)
INTRODUCTION
CAS Number 202409-33-4
Description
Etoricoxib is a synthetic, nonsteroidal anti-inflammatory drug
(NSAID) with antipyretic, analgesic, and potential antineoplastic
properties. Etoricoxib specifically binds to and inhibits the
enzyme cyclooxygenase-2 (COX-2), resulting in inhibition of the
conversion of arachidonic acid into prostaglandins.
Structure
Chemical
Formula
C18H15ClN2O2S
16

17. Mol. Weight 358.84 gm/mol
IUPAC Name
5-chloro-2-(6-methylpyridin-3-yl)-3-(4-methylsulfonyl) phenyl)
pyridine.
Categories
 COX-2 Inhibitors
 Anti-Inflammatory Agents
Solubility Slightly Soluble in water, freely soluble in methanol
Mechanism
Of Action
Like any other COX-2 selective inhibitor Etoricoxib selectively
inhibits isoform 2 of cyclo-oxigenase enzyme (COX-2),
preventing production of prostaglandins (PGs) from arachidonic
acid.
LogP 3.7
pKa 4.96
Melting point 134-135°C
17

18. 2. Drug profile of Pregabalin (15-16)
INTRODUCTION
CAS Number 148553-50-8
Description
Pregabalin is structurally similar to gamma-
aminobutyric acid (GABA) - an inhibitory
neurotransmitter. It may be used to manage
neuropathic pain, postherpetic neuralgia, and
fibromyalgia among other conditions
Structure
Chemical
Formula
C8H17NO2
18

19. Mol. Weight 259.22 gm/mol
IUPAC Name 3-isobutyl GABA, (S)-3-isobutyl-γ-aminobutyric acid
Categories
 Anticonvulsants
 Analgesics
Solubility Freely Soluble in water
Mechanism
Of Action
Act as a ligand of the alpha2-delta subunit of calcium channels.
Decreased calcium entry into nerve endings. less glutamate
released from nerve endings .than relief of neuropathic pain.
LogP -1.3
pKa 4.2
Melting point 176 - 178ºC
19

20. 3. REVIEW OF LITERATURE
20

21. 3. Review of Literature
 Official
Drugs Method Year Abstract Summary Ref. No
Etoricoxib Monograph IP
2010
Column: stainless steel column 30 cm x 3.9 mm,
packed with phenyl silica gel
Mobile phase : mixture of 26 volumes of
acetonitrile and 74 volumes of a 0.272 per cent
w/v solution of sodium acetate,
Flow rate: 1.0 ml/min
Wavelength: 256 nm
18
Pregabalin Monograph IP
2010
Column: stainless steel column 25 cm x 4.6 mm
packed with octadecylsilane bonded to porous
silica (5 μm)
Mobile phase : mixture of62 volumes of a buffer
solution prepared by diluting about 7.18 ml
of triethylamine to 1000 ml water, adjusted to pH
3.0 with orthophosphoric acid and 38 volumes
of acetonitrile,
Flow rate: 2.0 ml/min
Wavelength: 340 nm
19
21

22.  Non - official
Drugs Method Authors/year
/article /journal
Abstract Summary Ref. No
Etoricoxib RP-HPLC Bhattacharya I
Bhattacharya SP .
Asian J. Research
Chem
2009
297-299
Column: C18 column
Mobile Phase: phosphate buffer ( pH-7.8)
and methanol (90:10 v/v)
Wavelength: 235 nm., Flow rate: 1 ml/min
Retention times: 3.428 min
Linearity range: Etoricoxib - 10-200 μg/ml
20
Etoricoxib HPLC Haque M ,
Shaema N.
Am. J. Pharm Tech
Res.
2012
275 – 283
Column: C18 column (250 mm × 4.6 mm.
5μm particle size)
Mobile Phase: Ammonium Acetate
Wavelength: 235 nm., Flow rate: 1 ml/min
21
22

23. Drugs Method
s
authors/ year
/articals
Abstract Summary Ref.
No
Etoricoxib RP-
HPLC
Venugopal S,
Tripathi UM,
Devanna N,
E-Journal of
Chemistry
2011
S119-S126
Column : Zorbax SB CN (250 × 4.6 mm , 5µm)
Mobile phase : buffer : methanol
50:50
Flow rate : 0.8 ml/min
Wavelength : 235 nm
22
Pregabalin RP-
HPLC
Kasawar GR,
Faroogui MN .
Indian Journal of
Pharmaceutical
Sciences. 2010
517-519
Column: Hypersil BDS(C8, 150×4.6 mm,5 μm)
column
Mobile Phase: phosphate buffer pH 6.9 and
acetonitrile in the ratio of 95:05 Flow rate: 1 ml/min
23
Pregabalin RP-
HPLC
Prathima SSP.
INDO AMERICAN
JOURNAL OF
PHARMACEUTICAL
SCIENCES
2015
1038-1047
Column: AGILENT ZORBAX SB-ODS C18(250×4.6
mm)5 μm
Mobile Phase: dipotassium hydrogen phosphate:
methanol in the ratio of 60:40% v/v
Wavelength: 247 nm. ,Flow rate: 1 ml/minRetention
times: 2.00 min
Linearity range: 50 μg/ml to 150 μg/ml
LOQ: 0.53 𝜇g/ml LOD: 1.61 𝜇g/ml
24
23

24. Drugs Method Authors/year
/article /journal
Abstract Summary Ref.
No
Etoricoxib
(ETR) and
Thiocolchico
side (THC)
RP-
HPLC
Kumar US ,
Natraj D,
Khan A
INTERNATIONAL
JOURNAL OF
RESEARCH IN
PHARMACY AND
CHEMISTRY
2011
649-65
Column: C18 stainless steel column (InertSil
ODS-3, 250 mm x 4.6 mm ID, particle size 5μm)
Mobile Phase: phosphate buffer (PH6, adjusted
with ortho phosphoric acid) and methanol
(30:70 v/v)
Wavelength: 255 nm. , Flow rate: 1.2 ml/min
Retention times: Etoricoxib - 2.506 min
Thiocolchicoside - 4.600 min
Linearity range: Etoricoxib - 40-80 μg/ml
Thiocolchicoside 2-6 μg/ml
25
Paracetamol
(PCM) and
Etoricoxib
(ETO)
HPLC Baheti KG
Shaikh S
International
Journal of
PharmTech
Research vol -3
2011
1719-1727
Mobile Phase: phosphate buffer : acetonitrile
(60:40v/v)
Wavelength: 242 nm.
Retention times: PCM – 1.51 min
ETO – 4.31 min
Linearity range: PCM - 5-30 μg/ml
ETO 1-6 μg/ml
26
24

25. Drugs Method Authors/year
/article /journal
Abstract Summary Ref. No
NSAIDs
and their
commonly
prescribed
combinatio
n drugs
RP-HPLC Gananadhamu S,
Patel PN .
Chromatography
Research
International
2013
1-13
Column: Kromasil C18 (250 × 4.6 mm, 5 𝜇m)
Mobile Phase: phosphate buffer pH 3.25 and
acetonitrile with gradient elution
Wavelength: 230 nm.
Flow rate: 1.1 ml/min
LOQ: 0.64 to 3.24 𝜇g/Ml
LOD: 0.04 to 0.97 𝜇g/mL
27
Etoricoxib
and
Paracetam
ol
RP-HPLC Rao KP,
Damanu G .
Journal of Advanced
Studies in
Agricultural,
Biological and
Environmental
Sciences
2014
2394-2606
Column: Hypersil BDS C18 (250 x 4.6 mm
i.d., 5μm particle size)Mobile Phase: 0.05 M
sodium dihydrogen phosphate buffer
(adjusted pH 3.2 with o-phosphoric acid):
acetonitrile (35:65 v/v)
Wavelength: 235 nm.
Flow rate: 1 ml/min
concentration range:
Etoricoxib - 1000 to 3000μg/ml 40-80 μg/ml
Paracetamol - 1200 to 3600μg/ml
28
25

26. Drugs Method Authors/
year/ artical
Abstract Summary Ref. No
Thiocolchic
oside and
Etoricoxib
RP-HPLC Padmavati k,
Rao MS.
World Journal
of
Pharmaceutic
al Sciences.
2016
76-79
Column: Hypersil BDS C18 (250 x 4.6 mm i.d.,
5μm particle size)Mobile Phase: phosphate
buffer(pH-3.4) and acetonitrile in the ratio of
35:65 v/v
Wavelength: 260 nm., Flow rate: 1 ml/min
Retention times: Etoricoxib – 6.92 min
Thiocolchicoside – 2.83 min
29
Pregabalin
And
Methalcob
alamine
RP-HPLC Bhatt KK,
Patelia EM,
Mori A,
Journal of
Analytical &
Bioanalytical
Techniques
2018
1-4
Column : C18 ( 250× 4.6 mm) 5µm
Mobile phase : Methanol : water 40:60
Wavelength : 218 nm
Retension time : 6.4
PH :6.5
30
26

27. Drugs Method Authors / year
/ artical
Abstract Summary Ref.
No
Epalrestat
and
Pregabalin
RP-
HPLC
Parmeshweri
SA ,Anunam G.
International
Journal of
Pharmaceutica
l Sciences and
Research
2018
1844-1850
Column: C18 column 250 × 4.6 mm
Mobile Phase: 0.1% ortho phosphoric acid buffer and
acetonitrile ( ratio of 45: 55)
Wavelength: 244 nm. , Flow rate: 1 ml/min
Detector: PDA
Linearity range: Epalrestat - 37.5 – 225 μg/ml
Pregabalin - 18.75 - 112.5 μg/ml
Retention times: Epalrestat – 2.407 min
Pregabalin – 3.272 min
31
Nortriptyli
ne and
Pregabalin
RP-
HPLC
Potkuri H, Rao
SB.
Journal of the
Chilean
Chemical
Society.62
2017
62
Column: C18 column BDS (250mm x 4.6 mm, 5m)
Mobile Phase: Perchloric acid (0.1%) and acetonitrile
in the ratio of 55:45
Wavelength: 210 nm. , Flow rate: 1 ml/min
concentration range: nortriptyline – 37.5 - 22.5
μg/ml
Pregabalin - 37.5 – 22.5 μg/ml
Retention times: nortriptyline – 2.407 min
Pregabalin – 3.272 min
32
27

28. Drugs Method Authors
/year/art.
Abstract Summary Ref. No
Epalrestat
and
Pregabalin
RP-HPLC Goday S,
Ragaman A.,
Asian
journal of
pharmaceuti
cal and
clinical
reaserch,
vol -112018
319-324
Precision : epalrestat - 0.2% Pregabalin – 0.3%
LOQ : Epalrestat - 0.65 μg/ml
Pregabalin – 0.25 μg/ml
LOD : Epalrestat - 0.21 μg/ml
Pregabalin – 0.08 μg/ml
Linearity range: Epalrestat - 30–180 ppm
Pregabalin - 15–90 ppm
33
Pregabalin
and
Celecoxib
RP-HPLC Swapna G
Merugu M,
World
Journal of
Pharmaceuti
cal Research,
2017
1354-1360
Column: Hypersil BDS(150 mm x 4.6 mm, 5m)
Mobile Phase: potassium di hydrogen orthophosphate
buffer of pH 6.5 and acetonitrile in the ratio of (70:30)
Wavelength: 238 nm.
Flow rate: 1 ml/min
Linearity range: Celecoxib - 100 μg/ml -750 μg/ml
Pregabalin-37.5μg/ml-281.25 μg/ml
34
28

29. Drugs Method Author/year
/ artical
Abstract Summary Ref.
No
Pregabalin
and
Aeclofenac
stability
RP-HPLC
Suchitta TJ
Gurupadoyy
a B M .
Acta
scientific
Pharmaceuti
cal sciences.
2018
20-26
Wavelength: Aeclofenac - 276 nm., Pregabalin - 406 nm
concentration range: Aeclofenac – 10 - 50μg/ml μg/ml
Pregabalin - 50 - 500μg/ml μg/ml
LOQ: Aeclofenac - 2μg/ml , Pregabalin - 4μg/ml
LOD: Aeclofenac – 0.50 μg/ml ,Pregabalin – 0.6 μg/ml
35
Epalrestat
and
Pregabalin
stability-
indicating
RP-HPLC
Prasad R ,
Madhuharik
a MY.
International
journal of
pharmacy
2017
157-164
Column: C18 (150x4.6mm, 5μ) column
Mobile Phase: Ammonium acetate buffer (pH 10): ACN
70:30 % v/v , Flow rate: 1 ml/min
LOQ : Epalrestat - 0.57 μg/ml Pregabalin – 1.51
μg/ml , LOD : Epalrestat - 0.19 μg/ml Pregabalin –
0.50 μg/ml
Linearity range: Epalrestat - 37.5 – 225 μg/ml
Pregabalin - 18.75 - 112.5 μg/ml
Retention times: Epalrestat – 2.516 min
Pregabalin – 3.132 min
36
29

30. Drugs Method Authors /year/
articals/
journal
Abstract Summary Ref.
No
Etoricoxib
and
Drotaveri-ne
RP- HPLC Syal PK, Sahoo
M, Ingale KD,
Ingale SS,
Choudhari VP
And Kuchekar
BS,
Scholars
Research Library
2010
93-102
Column: kramosil C18 ( 250 × 4.6 mm,
5µm)
Mobile phase : methanol: buffer
51:49
Flow rate : 0.9 ml/min
Wavelength : 244 nm
37
Pregabalin
And
Nor-
triptiline
RP- HPLC Mewada NA,
Patel BR, Patel
JG, Vegad KL and
Patel VS,
International
Journal for
Pharmaceutical
Research
Scholars
2017
1-7
Column : BDS Hypersil C18 column
(250×4.6 mm ,5 µm)
Mobile Phase : buffer : methanol
70:30
Flow rate : 1 ml /min
Wavelength : 210nm
38
30

31. Drugs Method Authors /year/
articals/ journal
Abstract Summary Ref. No
Epalrestat
and
Pregabalin
RP-HPLC Sivagami I,
Kavyalalitha S,
INTERNATIONAL
RESEARCH
JOURNAL OF
PHARMACY
2018
9
Column: C8 (250 x 4.6 mm, 5μm) Column.
Mobile Phase: Potassium Dihydrogen
Phosphate Buffer: Acetonitrile taken in the
ratio 45:55
Flow rate: 1 ml/min, Wavelength: 274 nm
LOQ : Epalrestat - 0.73 μg/ml
Pregabalin – 0.07 μg/ml
LOD : Epalrestat - 0.24 μg/ml
Pregabalin – 0.02 μg/ml
Retention times: Epalrestat – 2.373 min
Pregabalin – 2.967 min
39
31

32. 4. REFERENCES
32
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33. 33
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34. 34
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Pregabalin In Pharmaceutical Dosage Forms By RP-HPLC.” Indo American Journal of
Pharmaceutical Science. 2015, 2(6),1038-1047
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Dosage Forms.” International journal of research in pharmacy and chemistry. 2011,
649-655.

35. 35
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1844-1850.

36. 36
32. Potluri1 H and Rao SB, “Validated Stability Indicating RP-HPLC Method For
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37. 37
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38. 38