Transcript Slide 1

Setting Impurity Standards for APIs and Dosage Forms: An IP Perspective

Dr Saranjit Singh

National Institute of Pharmaceutical Education and Research SAS Nagar 160 062 India [email protected]

Indian Pharmacopoeia

Available Edition: 1996

Supplements: 2000, 2002 and 2005

Control of Impurities in IP 1996 and Supplements

Tests for Related Substances

Specific Tests for the Named Impurities

General Tests for Unnamed Impurities

Total Impurity limits

Test Design and Expression of Limits for Known and Unknown Impurities

IP 1996

Total number of monographs Monographs with HPLC assay methods Monographs with Test for Related Substances TLC methods HPLC methods

1253 139 448 391 57

A Typical Example - TLC Method

Indian Pharmacopoeia Commission

IPC

Established: 9 December 2004

Mandate of IPC

To bring new editions and supplements of Indian Pharmacopoeia at regular intervals

To accelerate the process of preparation, certification and distribution of IP reference substances

To develop understanding with International Pharmacopoeial agencies

Vision Statement of

(Adopted 8 July 2006)

IPC

‘To promote the highest standards for drugs for use in humans and animals within practical limits of the technologies available for manufacture and analysis’

Why mention of:

……..practical limits of technologies available for manufacture and analysis?

Indian industry is fragmented into:

    Indian multinationals Large Companies Medium sized Small scale In total

5500

enterprises, with differences in technological capability for manufacture and analysis

Regulatory laboratory set-up is also fragmented:

   Central Laboratories State Laboratories Approved Private Test Laboratories Presently

differ in technological capability for analysis

, though Central/State Laboratories are being upgraded with same brands of state-of-art sophisticated analytical instruments under Capacity Building Project

Other local compulsions

 Large population of the country

~1.2 billion

 Very low gross national income

~$620

(US $41,400) 

390 million

live on less than

$1

a day  Population below poverty line:

25-29%

80%

of the health care payments borne by individuals

So important for the Government to ensure continued supply of medicines at an affordable cost Price comparison of some well known drugs in INR Drug Name Ciprofoxacin 500 mg (10s) Norfloxacin 400mg (10s) Diclofenac 50 mg (10s) Price in India 29.00

20.70

3.50

Pakistan

Source: OPPI website, 45 INR = 1$

Price in 423.86

168.71

84.71

Price in Indonesia 393.00

130.63

59.75

Price in US 2352.35

1843.66

674.77

In this scenario

The drug quality standards need to be rational, practical and simple The products sold in the country presently comply to standards laid down in

Indian Pharmacopoeia 1996

, the monographs of which meet the above requirements

The perspectives of

IPC

on impurities in pharmaceuticals in future editions of compendia

An objective of

(Adopted 8 July 2006)

IPC

‘To give special attention to the methods of manufacture used by the indigenous industry in selecting the pharmacopoeial tests for monitoring the

toxic

impurities of the concerned drug.’

Basic decisions of

IPC

on Impurities

 Minimum change in existing monographs  For new monographs, impurity control directed to be a part of Related Substances test  Both TLC and HPLC methods acceptable  Stringent limit, if an impurity is toxic and/or named impurity is to be controlled (e.g., N,N dimethylalinine in cloxacillin sodium, <20ppm)

Other perspectives of

IPC

on Impurities

 IPC to take care that Related Substances test in new monographs received from industry has no barrier element  In all situations, the test must be possible in Government and Private Laboratories

IP 2007: INTRODUCTION

“The use of chromatographic methods has been greatly extended to cope with the need for more specificity in assays and in particular, in assessing the nature and extent of impurities in ingredients and products”

IP 1996 versus 2007

Total number of monographs Monographs with HPLC assay methods Monographs with test of Related Substances TLC methods HPLC methods 1996

1253 139

2007

1253 -13 +257 = 1497 139+…… 448 448+~100 391 57 ~390 57+~100

IP 2007 General Chapter on Impurities 5.5 Impurities

This chapter provides guidance on the control of impurities in drug substances and formulated preparations. It applies mainly to totally synthetic organic medicinal substances and those substances obtained by synthetic modification of a naturally produced precursor; it is not necessarily relevant to other organic substances e.g. those of plant or animal origin, biological and biotechnological products, inorganic substances and pharmaceutical excipients. It provides an approach to the setting of limits for impurities in articles for which the individual monographs do not provide either a test or specific limits. An impurity is defined as any component of a drug substance for pharmaceutical use or of a drug product that is not the chemical entity that defines the substance, or in the case of a

General Chapter

Acceptance criteria for impurities in drug

substances: Each identified impurity specified Not more than 0.5

per cent Each unidentified impurity Not more than 0.3

per cent Total impurities Not more than 1.0 per cent Provided it has been determined that the impurities are not toxic. Higher limits may be set if scientifically justified.

General Chapter

(cont…) Acceptance criteria for degradation products in drug products:

Each identified product degradation Each unidentified degradation products Total degradation products Not more than 1.0

per cent Not more than 0.5 per cent Not more than 2.0

per cent Provided it has been determined that the impurities are not toxic. Higher limits may be set if scientifically justified.

Viewpoints in the General Chapter

‘Although a primary objective of the Pharmacopoeia is to guarantee the identity, strength, purity and quality of official articles,

it is not possible to include in each monograph a test for every impurity or contaminant or even an adulterant that might be present

Viewpoints in the General Chapter (cont..)

“The exclusion of a limit for impurities in a monograph does not absolve the manufacturer of providing assurance to the user on the safety of a drug.

It is incumbent on the manufacturer to follow good manufacturing practices (GMP) and to ensure the limitation of impurities based on knowledge of the properties of the chemical entity and the likelihood of related substances being associated with the end product during production and subsequent storage.

Viewpoints in the General Chapter (cont..)

“Material found to contain an impurity not detectable by pharmacopoeial the prescribed quality tests particularly if of a monograph may be deemed to be not of the nature of the impurity(ies) compatible with GMP.

found is not In any case, the specifications should in course of time be refined to include tighter and more specific limits in the light of experience with production batches and a better understanding of the manufacturing process.

So, an overall perspective of

IPC

CONTROL OF IMPURITIES is more stronger regulatory and GMP issue, than compendial So only reasonable control in IP,

except for those related substances that are known or even doubted to adversely influence safety of the product

What

IPC

aspires for

Information on impurities associated with side effects or toxic reactions, including genotoxicity,

so that specific named tests can be added in existing or new monographs of Indian Pharmacopoeia

Simple tests

for these impurities

Current Dynamics of Indian Pharmaceutical Industry

Top Indian Companies – Way Ahead

 Export oriented Indian companies, which have world class facilities, completely comply to stringent International regulatory expectations on impurities  Some of the Indian companies have more than 600 HPLC systems, change 100 columns per day, and are equipped with most sophisticated instruments, like LC-MS, LC NMR, etc., which are being used for impurity profiling and structure characterization

An Example of Maturity of Indian Industry FDAnews Drug Daily Bulletin Nov. 16, 2007 | Vol. 4 No. 226 Generic Firm Commences Gabapentin Recall Due to Excessive Impurities Ranbaxy Pharmaceuticals

initiated a voluntary Class III recall of

73 million gabapentin tablets

because the allowed level of impurities in the tablets exceeded their specification limits, according to FDA documents. Gabapentin is the active ingredient in Pfizer’s antiseizure drug Neurontin, which is off patent. The affected dosage strengths include the 600- and 800-mg tablets. Ranbaxy’s abbreviated new drug application (ANDA) for the tablet formulation is for those two strengths and the firm holds approval for a capsule formulation as well.

The company could not comment on whether the recall will create a shortage of its tablets.

A Few Distinct Advantages

 The drive of export-oriented Indian Pharma companies, to meet stringent quality and impurity control expectations of International agencies, has lead not only to creation of excellent facilities and trained manpower, it has been indirectly responsible for improvement of quality of pharmaceuticals sold within the country, as the same companies hold 70% share in the local market 

This is happening without intervention of local pharmacopoeial and regulatory agencies

The Benefit of Indian System as a Whole

The Indian system encourages the big players, but it also protects medium and small scale enterprises, which are very much needed in the chain of supply of drugs to large population of the country with marked differences in paying capacities

Summing up…

For a country with >1.2 billion people The priority is AVAILABILITY of GOOD QUALITY DRUGS at AN AFFORDABLE COST

Our belief is…

GOOD QUALITY of drugs and products can be well assured by recently adopted approach of

IPC

on impurities

Somehow…

We at

IPC

are not fully convinced on the trend in USP, EP, BP, etc. on searching impurities in each and every product, even old and well established, at ICH thresholds, which we consider is guided more by

protectionist approach

of big players in Pharmaceutical industry

A glimpse of emerging standards….

European Pharmacopoeia 5.0, 2005

EP 5.0

(2005) (Ph Eur monograph 0906

)

Due to

tropical environmental conditions

in India, it may not be reasonable to expect Industry to control individual degradation products in formulations at

0.1 or 0.15%

Moreover, a moot point….

If there is no

emphasis

on impurities in

kilogram(s)

and

liters of food

taken by an individual in a day Then how come it is a so

serious issue

consumed in a for few

milligrams of drug(s) tiny pill

daily?

So overall,

1. There is a need to ponder whether the

forensic analysis of pharmaceuticals

is all that necessary 2. Something, which is

real toxic

and difficult for our bodies to handle, must be controlled but

not every type of minutiae

3. The compendia require

innovative thinking

, wherein impurities are classified drug-wise as ‘toxic’ and ‘safe’, with emphasis only on those that might be harmful 4. Compendia must pursue

policy of exclusion

currently rather than inclusion, unlike the trend being pursued

Thanks so much