Working document QAS/16.678

August 2016

Draft for comments

1 2

CLINDAMYCIN PHOSPHATE 3

(CLINDAMYCINI PHOSPHAS) 4

REVISED DRAFT MONOGRAPH FOR INCLUSION IN 5

The International Pharmacopoeia 6

(August 2016) 7

DRAFT FOR COMMENTS 8

9 Gg 10

DRAFT FOR COMMENTS 11

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18 19 20 21

© World Health Organization 2016 22

All rights reserved. 23

This draft is intended for a restricted audience only, i.e. the individuals and organizations having received this draft. 24 The draft may not be reviewed, abstracted, quoted, reproduced, transmitted, distributed, translated or adapted, in 25 part or in whole, in any form or by any means outside these individuals and organizations (including the 26 organizations' concerned staff and member organizations) without the permission of the World Health Organization. 27 The draft should not be displayed on any website. 28

Please send any request for permission to: 29 Dr Sabine Kopp, Group Lead, Medicines Quality Assurance Programme, Technologies Standards and Norms, 30 Department of Essential Medicines and Health Products, World Health Organization, CH-1211 Geneva 27, 31 Switzerland. Fax: (41-22) 791 4730; email: kopps@who.int. 32

The designations employed and the presentation of the material in this draft do not imply the expression of any 33 opinion whatsoever on the part of the World Health Organization concerning the legal status of any country, 34 territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. Dotted lines 35 on maps represent approximate border lines for which there may not yet be full agreement. 36

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This draft does not necessarily represent the decisions or the stated policy of the World Health Organization. 44

45

Should you have any comments on this draft, please send these to Dr Herbert Schmidt,

Medicines Quality Assurance Programme, Technologies, Standards and Norms, Department of

Essential Medicines and Health Products, World Health Organization, 1211 Geneva 27,

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Working document QAS/16.678

page 2

SCHEDULE FOR THE ADOPTION PROCESS OF DOCUMENT QAS/16.678: 46

Clindamycin phosphate (Clindamycini phosphas) 47

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Date

Revision drafted by a WHO Collaborating

Centre

October 2015–January 2016

Discussion at informal consultation on

quality control laboratory tools and

specifications for medicines

9–11 May 2016

Draft revision sent out for public

consultation

August–October 2016

Presentation to WHO Expert Committee on

Specifications for Pharmaceutical

Preparations for possible adoption

October 2016

Further follow-up action as required

Working document QAS/16.678

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CLINDAMYCIN PHOSPHATE 57

(CLINDAMYCINI PHOSPHAS) 58

59

[Note from the Secretariat. Changes from the current monograph are indicated in the 60

text by insert or delete.] 61

62

63

64

C18H34ClN2O8PS 65

66

Relative molecular mass. 505.0 67

68

Chemical name 69

70

Methyl 71

7-chloro-6,7,8-trideoxy-6-[[[(2S,4R)-1-methyl-4-propylpyrrolidin-2-yl]carbonyl]amin72

o]-2-O-phosphono-1-thio-L-threo-α-D-galacto-octopyranoside (2S-trans)-Methyl 73

7-chloro-6,7,8-trideoxy-6-(1-methyl-trans-4-propyl-L-2-pyrrolidinecarboxamido)-1-t74

hio-L-threo-α-D-galacto-octopyranoside 2-(dihydrogen phosphate); CAS Reg. No. 75

24729-96-2. 76

77

Description. A white or almost white, crystalline powder. 78

79

Solubility. Freely soluble in water; very slightly soluble in ethanol (~750 g/L) TS and 80

acetone R, practically insoluble in dichloromethane R. 81

82

Category. Antibacterial drug. 83

84

Storage. Clindamycin phosphate should be kept in a tightly closed container. 85

86

Labelling. The designation Clindamycin phosphate for parenteral use indicates that 87

the substance complies with the additional requirements and may be used for 88

parenteral administration. Expiry date. 89

90

91

Working document QAS/16.678

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Additional information. Clindamycin phosphate is slightly hygroscopic and may 92

exhibit polymorphism. It is a semi-synthetic product derived from a fermentation 93

product. 94

95

Requirements 96

97

Clindamycin phosphate contains not less than 96.0%95.0% and not more than 102.0% 98

100.5% of C18H34ClN2O8PS, calculated with reference to the anhydrous substance. 99

100

• Either tests A and D or tests B, C and D may be applied. 101

102

A. Carry out the examination as described under 1.7 Spectrophotometry in the 103

infrared region. The infrared absorption spectrum is concordant with the 104

spectrum obtained from clindamycin phosphate RS or with the reference 105

spectrum of clindamycin phosphate. If the spectra thus obtained are not 106

concordant repeat the test using the residues obtained. Separately dissolve the 107

test substance and clindamycin phosphate RS in a small amount of water R and 108

heat until the substances are completely dissolved. Evaporate to dryness under 109

reduced pressure and dry the residues at 100–105 °C for 2 hours. The infrared 110

absorption spectrum is concordant with the spectrum obtained from clindamycin 111

phosphate RS. 112

113

B. Carry out the test as described under 1.14.1 Thin-layer chromatography using 114

silica gel R3 as the coating substance and a mixture of 6 volumes of 1-butanol R, 115

2 volumes of water and 2 volumes of glacial acetic acid R as the mobile phase. 116

Apply separately to the plate 5 μL of each of 3 solutions in methanol R 117

containing (A) 2.0 mg of Clindamycin phosphate per mL, (B) 2.0 mg of 118

clindamycin phosphate RS and for solution (C) dissolve 10 mg of lincomycin 119

hydrochloride RS in 5 mL of solution B. After removing the plate from the 120

chromatographic chamber allow it to dry at 105 °C for 30 minutes and spray 121

with potassium permanganate (1 g/L) TS. Examine the chromatogram in 122

daylight. 123

124

The principal spot obtained with solution A corresponds in position, appearance 125

and intensity to that obtained with solution B. The test is not valid unless the 126

chromatogram obtained with solution C shows two clearly separated spots. 127

C. Dissolve 10 mg in 2 mL of hydrochloric acid (~70 g/L) TS and heat directly in a 128

flame for 1 minute; a disagreeable sulfurous odour is perceptible. Cool, add 4 129

mL of sodium carbonate (75 g/L) TS and 0.5 mL of sodium nitroprusside (45 130

g/L) TS; a violet-red ring is formed that fades quickly. 131

132

D. Boil 0.1 g under a reflux condenser with a mixture of 5 mL of sodium hydroxide 133

Working document QAS/16.678

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(~400 g/L) TS and 5 mL of water for 90 minutes. Cool and add 5 mL of nitric 134

acid (~1000 g/L) TS. Extract with three 15 mL quantities of dichloromethane R 135

and discard the extracts. Filter the aqueous layer through a paper filter; the 136

filtrate yields reaction B described under 2.1 General identification tests as 137

characteristic of orthophosphates. 138

139

Specific optical rotation. Use a 10 mg/mL solution and calculate with reference to 140

the anhydrous substance; = +115° to +130°. 141

Clarity and colour of solution. A solution of 0.040 g in 10 mL of 142

carbon-dioxide-free water R is clear and colourless. Dissolve 1.00 g in carbon 143

dioxide-free water R. Heat gently if necessary. Cool and dilute to 25.0 mL with 144

carbon dioxide-free water R. This solution is clear and colourless, when analysed as 145

described under 1.11.2 Degree of coloration of liquids, Method II. 146

[Note from the Secretariat. The chapter 1.11 Colour of liquids is currently under 147

revision. Reference is already made to the new test procedure to be added under the 148

section 1.11.2 Degree of coloration of liquids.] 149

150

Water. Determine as described under 2.8 Determination of water by the Karl Fischer 151

method, method A, using 0.2 g 0.5 g of the substance; the water content is not more 152

than 0.050 0.060 g/g. 153

154

pH value. pH of a 10 mg/mL solution in carbon-dioxide-free water R, 3.5–4.5. 155

156

Related substances. Carry out the test as described below under "Assay". 157

Inject alternately 20μl each of solutions A and D. Continue the recording of the 158

chromatogram until clindamycin is eluted. 159

Measure the areas of the peak responses obtained in the chromatograms from 160

solutions A and D, and calculate the content of the related substances as a percentage. 161

In the chromatogram obtained with solution A, the area of any peak, other than the 162

principal peak or any peak corresponding to the solvent, is not greater than 2.5 times 163

the area of the principal peak obtained with solution D (2.5%). The sum of the areas 164

of all the peaks, other than the principal peak or any peak corresponding to the solvent, 165

is not greater than 4 times the peak corresponding to clindamycin phosphate obtained 166

with solution D (4.0%). 167

Carry out the test as described under 1.14.4 High-performance liquid chromatography 168

using a stainless steel column (15 cm × 4.6 mm) packed with end-capped particles of 169

silica gel, the surface of which has been modified with chemically-bonded 170

octadecylsilyl groups (5 µm).1 171

172

Use the following conditions for gradient elution: 173

1 A Symmetry C18 column was found suitable.

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174

mobile phase A: 21 volumes of acetonitrile for chromatography R and 79 175

volumes of phosphate buffer pH 6.0; 176

mobile phase B: 60 volumes of acetonitrile for chromatography R and 40 177

volumes of phosphate buffer pH 6.0. 178

179

Prepare the phosphate buffer pH 6.0 by dissolving 13.6 g of potassium dihydrogen 180

phosphate R in 750 mL of water R, adjust the pH to 6.0 with potassium hydroxide 181

(~450 g/L) TS and dilute to 1000 mL with water R. 182

183

Time

(min)

Mobile phase

A

(% v/v)

Mobile phase

B

(% v/v)

Comments

0–13 100 0 Isocratic

13–18 100 to 50 0 to 50 Linear gradient

18–39 50 50 Isocratic

39–40 50 to 100 50 to 0 Return to initial

composition

40–55 100 0 Re-equilibration

184

Operate with a flow rate of 1.1 mL per minute. As a detector use an ultraviolet 185

spectrophotometer set at a wavelength of 210 nm. Maintain the column temperature at 186

30 °C. 187

188

Prepare the following solutions in mobile phase A. 189

190

For solution (1) dissolve about 30 mg of the test substance and dilute to 10 mL. For 191

solution (2) dilute 1.0 mL of solution (1) to 200.0 mL. For solution (3) dilute 2.0 mL 192

of solution (2) to 10.0 mL. For solution (4) dissolve 3.0 mg of clindamycin phosphate 193

for system suitability RS (containing clindamycin phosphate and the impurities B, E, 194

F, G, I, J, K and L) and dilute to 1.0 mL. 195

196

Inject 20 μL of solution (4). 197

198

Use the chromatogram obtained with solution (4) and the chromatogram supplied 199

with clindamycin phosphate for system suitability RS to identify the peaks due to the 200

impurities B, E, F, G, I, J, K and L. The impurities are eluted at the following relative 201

retention with reference to clindamycin phosphate (retention time about 12 minutes): 202

impurity F about 0.15; impurity G about 0.19; impurity I about 0.34; impurity B about 203

0.45; impurity L about 0.64; impurity J about 1.20; impurity E about 1.73; and 204

impurity K about 1.90. 205

206

The test is not valid unless the resolution between the peaks due to impurity F and the 207

Working document QAS/16.678

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peak due to impurity G is at least 2.0. 208

209

Inject alternately 20 μL each of solution (1), (2) and (3). 210

211

In the chromatogram obtained with solution (1): 212

213

the area of any peak corresponding to either impurity B or L is not greater than 214

2 times the area of the principal peak in the chromatogram obtained with 215

solution (2) (1.0%); 216

the area of any peak corresponding to either impurity E or F is not greater than 217

the area of the principal peak in the chromatogram obtained with solution (2) 218

(0.5%); 219

the area of any peak corresponding to either impurity G, I, J or K is not greater 220

than 5 times the area of the principal peak in the chromatogram obtained with 221

solution (3) (0.5%); 222

the area of any other impurity peak is not greater than the area of the principal 223

peak in the chromatogram obtained with solution (3) (0.10 %); 224

the sum of the areas of all impurities is not greater than 4 times the area of the 225

principal peak in the chromatogram obtained with solution (2) (2.0 %). 226

Disregard any peak with an area less than 0.5 times the area of the principal 227

peak in the chromatogram obtained with solution (3) (0.05 %). 228

Assay. Determine as described under 1.14.4 High-performance liquid 229

chromatography, using a stainless steel column (25cm × 4.6mm) packed with 230

particles of silica gel, the surface of which has been modified with chemically bonded 231

octadecylsilyl groups (5-10μm). As the mobile phase, use a mixture of 8 volumes of 232

potassium dihydrogen phosphate (13.6 g/l) TS adjusted to pH 2.5 with phosphoric 233

acid (~105 g/l) TS and 2 volumes of acetonitrile R. 234

Prepare the following solutions in the mobile phase: solution (A) 3.0 mg of 235

Clindamycin phosphate per mL; solution (B) 3.0 mg of clindamycin phosphate RS per 236

mL; for solution (C) dissolve 5mg of lincomycin hydrochloride RS and 15.0 mg of 237

clindamycin hydrochloride RS in 5.0 mL of solution B and dilute with sufficient 238

mobile phase to produce 100 mL; and for solution (D) dilute 1.0 mL of solution B 239

with sufficient mobile phase to produce 100 mL. 240

Operate with a flow rate of 1.0 mL per minute. As a detector use an ultraviolet 241

spectrophotometer set at a wavelength of about 210nm. 242

Inject 20μl of solution C. 243

The assay is not valid unless the first peak (lincomycin) is clearly separated from the 244

solvent peak, and the resolution between the second peak (clindamycin phosphate) 245

and the third peak (clindamycin) is at least 6.0. The assay is valid only if the 246

symmetry factor of the clindamycin phosphate peak is not greater than 1.5. 247

Working document QAS/16.678

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Inject 20μl of solution B. If necessary adjust the integrator parameters. 248

Inject alternately 20μl each of solutions A and B. 249

Measure the areas of the peak responses obtained with solutions A and B, and 250

calculate the percentage content of C18H34ClN2O8PS. 251

Carry out the test as described under 1.14.4 High-performance liquid chromatography 252

using a stainless steel column (15 cm × 4.6 mm) packed with end-capped particles of 253

silica gel, the surface of which has been modified with chemically-bonded 254

octadecylsilyl groups (5 µm).2 255

256

As the mobile phase use a mixture of 21 volumes of acetonitrile for chromatography 257

R and 79 volumes of phosphate buffer pH 6.0. Prepare the phosphate buffer pH 6.0 by 258

dissolving 13.6 g of potassium dihydrogen phosphate R in 750 mL of water R, adjust 259

the pH to 6.0 with potassium hydroxide (~450g/L) TS and dilute to 1000 mL with 260

water R. 261

262

Prepare the following solutions in mobile phase. For solution (1) dissolve about 30 263

mg of the test substance and dilute to 10 mL. For solution (2) dissolve 30 mg of 264

Clindamycin phosphate and dilute to 10.0 mL. For solution (3) use a solution 265

containing 0.12mg lincomycin per mL and 0.24 mg of clindamycin phosphate RS per 266

mL 267

268

Operate with a flow rate of 1.1 mL per minute. As a detector use an ultraviolet 269

spectrophotometer set at a wavelength of 210 nm. 270

Inject 20 μl of solution (3). In the chromatogram the following peaks are eluted at the 271

following relative retentions with reference to clindamycin phosphate (retention time 272

about 8.0 minutes): lincomycin about 0.32.The assay is not valid unless the resolution 273

between the peaks due to clindamycin phosphate and lincomycin is at least 7.0. 274

Inject alternately 20 μL each of solutions (1) and (2). 275

276

Measure the areas of the peaks corresponding to clindamycin phosphate obtained in 277

the chromatograms from solutions (1) and (2) and calculate the percentage content of 278

clindamycin phosphate (C18H34ClN2O8PS), using the declared content of clindamycin 279

phosphate (C18H34ClN2O8PS) in clindamycin phosphate RS 280

281

Additional requirements for Clindamycin phosphate for parenteral use 282

283

Complies with the monograph for Parenteral preparations. 284

285

Bacterial endotoxins. If intended for use in the manufacture of a parenteral dosage 286

form without a further appropriate procedure for the removal of bacterial endotoxins, 287

2 A Symmetry C18 column was found suitable.

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carry out the test as described under 3.4 Test for bacterial endotoxins; contains not 288

more than 0.6 IU of endotoxin RS per mg of clindamycin. 289

290

Sterility. If intended for use in the manufacture of a parenteral dosage form without a 291

further appropriate sterilization procedure, complies with 3.2 Test for sterility. 292

293

Impurities 294

295

296

A. Methyl 297

6,8-dideoxy-6-[[[(2S,4R)-1-methyl-4-propylpyrrolidin-2-yl]carbonyl]amino]-1-th298

io-D-erythro-α-D-galacto-octopyranoside (lincomycin) (degradation product) 299

300

301

B. Methyl 302

7-chloro-6,7,8-trideoxy-6-[[[(2S,4R)-4-ethyl-1-methylpyrrolidin-2-yl]carbonyl]a303

mino]-2-O-phosphono-1-thio-L-threo-α-D-galacto-octopyranoside (clindamycin 304

B-2-phosphate) (synthesis-related impurity) 305

306

307

C. Methyl 308

7-chloro-6,7,8-trideoxy-6-[[[(2S,4R)-1-methyl-4-propylpyrrolidin-2-yl]carbonyl]309

amino]-3-O-phosphono-1-thio-L-threo-α-D-galacto-octopyranoside 310

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(clindamycin-3-phosphate) (synthesis-related impurity) 311

312

313

D. Methyl 314

7-chloro-6,7,8-trideoxy-6-[[[(2S,4R)-1-methyl-4-propylpyrrolidin-2-yl]carbonyl]315

amino]-4-O-phosphono-1-thio-L-threo-α-D-galacto-octopyranoside 316

(clindamycin-4-phosphate) (synthesis-related impurity) 317

318

319

E. Methyl 320

7-chloro-6,7,8-trideoxy-6-[[[(2S,4R)-1-methyl-4-propylpyrrolidin-2-yl]carbonyl]321

amino]-1-thio-L-threo-α-D-galacto-octopyranoside (clindamycin) 322

(synthesis-related impurity / degradation product) 323

324

325

F. Methyl 326

6,8-dideoxy-6-[[[(2S,4R)-1-methyl-4-propylpyrrolidin-2-yl]carbonyl]amino]-2-O327

-phosphono-1-thio-D-erythro-α-D-galacto-octopyranoside (lincomycin 328

2-phosphate) (degradation product) 329

330

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331

G. Methyl 332

6,8-dideoxy-2,4-O-(hydroxyphosphoryl)-6-[[[(2S,4R)-1-methyl-4-propylpyrrolidi333

n-2-yl]carbonyl]amino]-1-thio-D-erythro-α-D-galacto-octopyranoside 334

(2,4-phosphatidyl lincomycin) (synthesis-related impurity) 335

336

337

H. Methyl 338

7-chloro-6,7,8-trideoxy-6-[[[(2S,4R)-1-methyl-4-propylpyrrolidin-2-yl]carbonyl]339

amino]-2,3-di-O-phosphono-1-thio-L-threo-α-D-galacto-octopyranoside 340

(clindamycin-2,3-bisphosphate) (synthesis-related impurity) 341

342

343

I. Methyl 344

7-chloro-6,7,8-trideoxy-6-[[[(2S,4R)-1-methyl-4-propylpyrrolidin-2-yl]carbonyl]345

amino]-2,4-di-O-phosphono-1-thio-L-threo-α-D-galacto-octopyranoside 346

(clindamycin 2,4-bisphosphate) 347

348

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349

J. Methyl 350

7-chloro-6,7,8-trideoxy-6-[[[(2S)-1-methyl-4-propylidenepyrrolidin-2-yl]carbony351

l]amino]-2-O-phosphono-1-thio-L-threo-α-D-galacto-octopyranoside 352

(propylidene analog of clindamycin 2-phosphate) 353

354

355

K. 2,2′-Oxybis(hydroxyphosphoryl)bis[methyl 356

7-chloro-6,7,8-trideoxy-6-[[[(2S,4R)-1-methyl-4-propylpyrrolidin-2-yl]carbonyl]357

amino]-1-thio-L-threo-α-D-galacto-octopyranoside] (diclindamycin 358

pyrophosphate) 359

360

361

L. Methyl 362

7-chloro-6,7,8-trideoxy-6-[[[(2S,4R)-1-methyl-4-propylpyrrolidin-2-yl]carbonyl]363

amino]-2-O-phosphono-1-thio-D-erythro-α-D-galacto-octopyranoside 364

(7-epiclindamycin 2-phosphate) (degradation product) 365

366

367

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368

Reagents to be established 369

370

Potassium hydroxide (~450g/L) TS 371

372

A solution of potassium hydroxide R containing about 450 g of KOH per litre. 373

374

375

*** 376