SIGNIFICANCE OF PHARMACEUTICAL FACTORS ON SELECTION OF BIOBATCH

SIGNIFICANCE OF PHARMACEUTICAL FACTORS ON SELECTION OF BIOBATCH

Jayshil A. Bhatt and Ramesh K. Goyal ^*

Institute of Life Sciences, Ahmadabad University, Ahmadabad - 380009, Gujarat, India.

ABSTRACT: Biobatch is usually prepared for the purpose of pharmacokinetic evaluation before NDA or IND filing. There are several critical issues that one has to face during the audit process like equivalence between the Biobatch and proposed commercial production batch. During the development and scale-up of the manufacturing process, various standard operating processes have to be documented to provide link between the bio/clinical batch and commercial batch. The Biobatch is a key component of the quality assessment, regardless of whether there is a bio waiver supported by dissolution studies or a formulation comparison, or bioequivalence study. IVIVC is one of the methods accepted by regulatory authorities including USFDA and it is applied while preparing the Biobatch. Extensive pilot experiments are to be carried out before a Biobatch is prepared. This may increase the cost of production for the company. Further, even after the approval of the formulation, various pharmaceutical factors may vary and lead to inconsistencies during the production phase. Recently, to overcome these problems, several software are available. Judicious use of the comprehensive software coupled with suitable in-vitro testing may provide an economical solution for the preparation of a Biobatch. Among various software ‘Gastroplus’ is one of the best software  that predicts the absorption pattern, pharmacokinetics, and pharmacodynamics for drugs administered via intravenous, oral, ocular, and pulmonary routes in human and preclinical species and may become must alternative for Bio studies.

Biobatch, Bio wavier, IVIVC, IND, NDA

INTRODUCTION: As per the WHO Biobatch is defined as the test batch used in the bio study to demonstrate bioequivalence, or used in the bio wavier to demonstrate similarily, as compare to the innovator product ¹. It is required for the purpose of submission to the regulatory authorities for either biowaivers or conduct BA/BE & clinical trial.

Biobatch is also called as Bio logical evaluation batch which is prepared for conducting clinical trial in NDA or ANDA application. After drugs successful preclinical toxicity and pharmacokinetic studies the drug has to be taken to the phase I clinical study because biological evaluation is necessary to prove efficacy and safety of drug in human body. Bioequivalence studies are normally required to be done for every new generic product in that test product tested against the innovator’s marketed product ^4-5. Bioequivalence are also required when the proposed marketed dosage form is different from the used clinical trial or when significant changes are made in the manufacture of the marketed formulation ⁶.

FIG. 1: STAGES OF DRUG DEVELOPMENT AND BIOBATCH

Preparation of Biobatch is a great challenge. It has to meet various parameters related to quality assessment from regulatory point of view. The manufacturer has to be careful to develop both production batch as well as the Biobatch.  Biobatch is in fact a representative of production batches having the same formulation and same manufacturing process with respect to equipment, process and controls and hence a subject of regulatory audit at every step.

Pharmaceutical development data, of Biobatch represent key information that is used throughout the quality assessment. To evaluate the critical control parameters and one requires details of unit operation, control analysis techniques and by fractional factorial designs are often used to challenge the tentative control limits established for the process at different stages.

After the regulatory submission of IND, NDA or ANDA application there is Pre- Approval Inspections conducted by FDA where sampling and analysis of the Biobatch is audited. There is audit of the raw data for its integrity, in-process and finished product testing records and specific product and process of Biobatch preparation. During ANDA approval audit Biobatch is compared with marketed batch including the field commercial process.

Significance of Bioequivalence in Preparation of Biobatch: There are several critical issues that one has to face during the audit process like equivalence between the Biobatch and proposed commercial production batch. If there is any differences it has to be discussed with regard to potential impact on product bioequivalence ⁹.

Therefore it is important that during development and scale-up of the manufacturing process, it has to be well documented so that a link between the bio/clinical batch and commercial batch can be established.

When there is Bio wavier, the Biobatch (BW or BE batch) is of prime importance to support the dossier with respect to bio availability and Bio equivalence. Bioavailability of a drug depends on various factors like route of administration and pharmaceutical factors and condition of the patient. There are several physiological steps which directly affect the bioavailability of drug when it is administered through oral route. The systemic absorption of an orally administered drug in a solid dosage form comprise of three distinct steps: disintegration of the drug product; dissolution of the drug in the fluids at the absorption site and transfer of drug molecule across the membrane lining the gastrointestinal tract into the systemic circulation.

For the therapeutic effect of an orally administered drug it must be absorbed in systemic circulation, so that any factor that affects any of these three steps can alter the drug's bioavailability. Hence, its therapeutic effect in the clinical trial may not match with the comparator drug/within regulatory requirement so biobatch selection is also important before conducting clinical trial.

Patient related factors can change bioavailability of drug and there may be patient to patient variation in results of bioavailability so Biobatch may not be dependent on such uncontrolled factors. Same thing may happen because of the influence of route of administration on bioavailability of drug.

Pharmaceutical Factors in Biobatch: Pharmaceutical Factors in a Bio Batch may be Formulation Related Factor or Technological Related Factor.

FIG. 2: FACTORS AFFECTING BIOBATCH SELECTION

Formulation Related Factors are involved in manufacture process. They include several steps and parameters as mentioned in the Ishikawa diagram Fig. 2 for tablet manufacturing. Here, Plant factor, Compressing, Drying, Granulation, Raw Materials, and Analytical Methods have own importance in tablet quality and uniformity threw out manufacturing.

FIG. 3: ISHIKAWA DIAGRAM FOR DIFFERENT FACTORS AFFECTING DURING TABLET MANUFACTURING ¹¹

As it can be seen from the Ishikawa diagram, there can be a large number of variables. Any of these variables can change the dissolution profile hence, bio batch result may vary and batch uniformity may not be maintained. To maintain the batch uniformity and drug quality good manufacturing practice (GMP) and good laboratory Practices (GLP) guidelines have to be followed in Research and Development laboratory. There are guidelines available for GMP issue and by WHO and USFDA, It is mentioned that there must be standard operating procedure (SOP) for each process. For example in tablet manufacturing process during granulation mixer speed, chopper speed, temperature, spray rate, water concentration can make the difference. Thus, there is a need to follow SOP at each step and they should be updated as per the development into the process. During development of SOP, design of experiment (DOE) is also applied for optimization process and design space needs to be generated such that when any change is made, the drug uniformity is not affected.

Similarly, a change in any variable for dissolution profile of drug would affect the pharmacokinetics of the formulation. If drug is dissolved as per the time required or contains similar profile as reference drug than pharmacokinetic profile of drug might be within the acceptable limit. From the dissolution profile drugs pharmacokinetic parameter can be predicted using in vitro and in vivo Correlation ship (IVIVC). In vitro dissolution study is planned on the basis of human physiology so that better predictive result can be obtained.

Dissolution Testing in Biobatch: Dissolution testing is usually recommended as per USFDA guidelines. The dissolution methodology is developed, after setting specifications as per the the regulatory requirements.

• Dissolution testing of immediate release solid oral dosage forms ¹²;
• Extended release oral dosage forms: development, evaluation, and application of in-vitro/in-vivo correlations.

As per guideline the dissolution profiles, at least 12 individual dosage units from each lot should be determined. A suitable distribution of sampling points should be selected to define adequately the profiles. The coefficient of variation (CV) for mean dissolution profiles of a single batch should be less than 10%. Dissolution profiles is to be generated at different agitation speeds (e.g., 100 to 150 revolutions per minute (rpm) for U.S. Pharmacopeia (USP) Apparatus I (basket), or 50 to 100 rpm for USP Apparatus II (paddle)) ¹². The pH solubility profile of the drug is also important during dissolution test.

Importance of Dissolution for IVIVC: In-vitro dissolution testing is important test for, providing process control and quality assurance; determining stable release characteristics of the product over time; and facilitating certain regulatory determinations (e.g., absence of effect of minor formulation changes or change in manufacturing site on performance). In certain cases, especially for extended release formulations, the dissolution test can serve not only as a quality control for the manufacturing process but also as an indicator of how the formulation will perform in-vivo.

Bioequivalence is established between the generic product and the reference listed product at the highest and lowest strengths. For the reference listed product, all strengths are compositionally proportional or qualitatively same and have the same release mechanism, and the in vitro dissolution profiles are similar.

As per the regulatory requirements of ANDA application for bio similar drug, if the dissolution profile of test drug would match with reference drug than BA/BE study would not be required. Thus, dissolution is very important parameter of drug not only as Quality Control purpose but also for research and drug efficacy it is very important. More queries maybe expected during evaluation of dossier by FDA or during audit if the dissolution results are not supported by scientific justification. To control those queries Quality by Design (QbD) has to be implemented. QbD principles are applied on manufacturing or analytical testing like dissolution.

Stability Studies of Biobatch for its Equivalence: A key component of process validation may shows clinical or bio-batch equivalence. It is a frequent matter of discussion for all solid dosage form compliance inspection, since raw material variation can cause final product variation in uniformity, disintegration, hardness (tablets), and dissolution. It is desirable to use the same dosage form (tablet or capsule) for commercial batches as that used for Biobatches. This facilitates comparison of in-process testing result from validation batches to the bio- batches. Historically early R & D batches have utilized dry filled hard gelatine capsule for convenience if it differ from the final commercial dosage form.

To have a full scale production sufficient data should be collected during the bio-batches so that a comparison can be made with the full-scale demonstration batches or validation batches. Statement of equivalence is usually made by taking in to account the in-process results, raw material testing result and final product testing. It may be part of the validation report or in the conclusion of development report that includes the full scale data.

As per the ICH Q1A (R2) recommendations three primary batches of at least of the pilot scale sizes for the drug substance are filed in the DMF. These batches should be made under current good manufacturing practice (cGMP). Once a laboratory batch (often called 1X) has been determined to be both physically and chemically stable based on accelerated, elevated temperature testing (i.e. 1 month at 45 C or 3 month at 40 °C or 40 °C/ 80% RH), the stability guidance recommended a minimum of 6 months of accelerated data and 6 month of long term data for pilot scale batches are to be submitted initially in the DMF to support ANDA application.

Additional long term data for all three batches should be submitted as amendment. Testing time period for the accelerated storage condition has to include, a minimum of three time points including initial and final time points (e.g. 0, 3 and 6 months). For long-term studies, frequency of testing should be sufficient to establish the stability profile of the drug substance. For drug substances with a proposed retest period of at least 12 months, the frequency of testing at the long-term storage condition should normally be every 3 months over the first year, every 6 months over the second year, and annually thereafter through the proposed retest period ¹³.

Significance of IVIVC in Biobatch: IVIVC (a predictive mathematical model describing relationship of drug between an in-vitro property of a dosage form and an in-vivo response), is one of the methods accepted by regulatory authorities including USFDA. The purposes of application of IVIVC for biobatchis is reduction of regularity burden, optimization of formulation, justification for “therapeutic” product quality and quality control test for scale up and  post approval changes sometimes and cost saving during the product development. It works as surrogate for in-vivo bioequivalence and to support bio waivers (time and cost saving).

Thus, a main objective of developing and evaluating an IVIVC is to establish the dissolution test as a surrogate for human bioequivalence studies, which may reduce the number of bioequivalence studies performed during the initial approval process as well as with certain scale-up and post approval changes. However, for the applications outlined in ANDA, the adequacy of the in vitro dissolution method acts as a surrogate for in vivo testing should be shown through an IVIVC for which predictability has been established.

The expectations from IVIVC depend on the nature of drug based on BCS classification.

TABLE 1: IN-VITRO IN-VIVO CORRELATION POSSIBILITY IN BIOLOGICAL CLASSIFICATION SYSTEM ¹⁸

Based on regulatory guidelines, the in-vitro profiles are regarded acceptable for an IVIVC if the dissolution rate is a mean of twelve individual determinations and the coefficient of variation at each sampling point is less than 10%; however the initial release data may exhibit a larger variability ¹⁷.

IVIVC Established by Two Models for BioBatch: IVIVC for any dosage form can established by two model (1) Convolution model and (2) Deconvolution model. Convolution is the process of drug in the body to reflect blood drug concentration- time profile (right to left). On the other hand, extracting dissolution profiles from blood drug concentration-time profile is known as Deconvolution process (left to right).

FIG. 4: SCHEMATIC REPRESENTATION OF DECONVOLUTION AND CONVOLUTION PROCESS ¹⁸

It means in the development of convolution model the drug concentration time profile obtained from dissolution results may be evaluated using criteria for in-vivo bioavailability / bioequivalence assessment, based on C max and AUC parameter.

Deconvolution is a numerical method used to estimate the time course of drug input using a mathematical model based on the convolution integral. The Deconvolution technique requires the comparison of in-vivo dissolution profile which can be obtained from the blood profiles.

The observed fraction of the drug absorbed is estimated based on the Wagner-Nelson method or Loo-Riegelman. After optimizing the suitable model for Bio Batch evaluate the batch for prediction of in-vivo result by applying different method.

There are three types of IVIVC Correlation are established ^{15, 18} (1) Level A correlation: One to one relationship between in vitro and in-vivo data, e.g., in vitro dissolution vs. in-vivo absorption. (2) Level B correlation based on statistical moments, e.g., In vitro MDT vs. in-vivo MRT or MAT (3) Level C correlation means point to point relationship between a dissolution and a pharmacokinetic parameter, e.g., in-vitro T50% vs., in-vivo Tmax, Multiple C: relationship between one or several PK parameters and amount dissolved at several time points. In selection of BioBatch Level an IVIVC is considered to be the most informative and is recommended, if possible to establish. Level C correlations can be useful in the early stages of formulation development when pilot formulations are being selected but Level B correlations are least useful for regulatory purposes.

Establishment of Level an IVIVC in BioBatch: The most commonly seen process for developing a Level A IVIVC is to (1) Develop formulations with different release rates, such as slow, medium, fast, or a single release rate if dissolution is condition independent; (2) obtain in-vitro dissolution profiles and in-vivo plasma concentration profiles for these formulations; (3) Estimate the in-vivo absorption or dissolution time course using an appropriate deconvolution technique for each formulation and subject (e.g., Wagner-Nelson, numerical deconvolution). These three steps establish the IVIVC model. Alternative approaches to developing Level an IVIVCs are possible.

Methods for Evaluation of IVIVC model of BIOBATCH for Predictability: ¹⁹ All IVIVC model of BioBatch should be studied fist using internal predictability method. One recommended approach involves the use of the IVIVC model to predict each formulation’s plasma concentration profile (or C and/or AUC for max a multiple Level C IVIVC) from each respective formulation’s dissolution data. This is performed for each formulation used to develop the IVIVC model. The predicted bioavailability is then compared to the observed bioavailability for each formulation and a determination of prediction error is made. An acceptance criterion for internal predictability is average absolute percent prediction error (% PE) of 10% or less for Cmax and AUC establishes the predictability of the IVIVC.

In addition, the % PE for each formulation should not exceed 15%. If it was not satisfied than the internal predictability of the IVIVC is inconclusive. Another method is external predictability which is most important when using an IVIVC as a surrogate for bioequivalence. It gives the confidence that the IVIVC can predict in-vivo performance of subsequent lots of the drug product. Therefore, it may be important to establish the external predictability of the IVIVC. This involves using the IVIVC to predict the in-vivo performance for a formulation with known bioavailability that was not used in developing the IVIVC model. Acceptance criteria for external predictability result for BioBatch was % PE of 10% or less for C and AUC establishes the external max predictability of an IVIVC. % PE between 10 - 20% indicates inconclusive predictability and the need for further study using additional data sets.

Results of estimation of PE from all such data sets should be evaluated for consistency of predictability. % PE greater than 20% generally indicates inadequate predictability, unless otherwise justified. With the exception of narrow therapeutic index drugs, the external predictability step in the IVIVC evaluation process may be omitted if the evaluation of internal predictability indicates acceptable % PE.

However, when the evaluation of internal predictability is inconclusive, evaluation of external predictability is recommended.

Pharmacokinetic Software’s Use in BioBatch: There are several Pharmacokinetic software which are available to guide the scientist for preparation of BioBatch at every stage Table 1. These softwares provide the result on human Physiology based pharmacokinetic (PBPK), applied Principle of Bayesian estimation, in-silico, and IVIVC data. When new drug molecule is developed at that time acslXtreme and DDI Predict software help to give drug-drug interactions result between a drug candidate and a large panel of marketed or withdrawal drugs.

BioBatch statistical analysis for bioavailability and Bioequivalence studies with the help of BIOPAK software. There are different software like Bear, ATIS like which gives nonlinear regreation and optimal sampling technique for clinical studies. They also analysis average bioequivalence data from non compartmental analyze the ANOVA for crossover or repeated crossover design. Some softwares analyze average bioequivalence involves the calculation of 90% confidence intervals for the ratio of the measures for the test and reference products.

Gastroplus like software predicts the pharmacokinetic profile as per route of administration of drug. For generic drugs APIS like software helps to give pharmacokinetic data based on previous study patient information (population) to determine patient specific parameter estimate. From the different batches to select the BioBatch which had pharmaceutical stability can evaluate on Stab for R software. There are some software which also give rapid analysis and understanding of the behaviour of drug candidates in animal and human. Some software also gives food effect and effects of influx and efflux transporters in gut or any tissue. They also predict biopharmaceutical properties from chemical structure and also tracks multiple metabolites formed into body. The software predict steady-state and dynamic drug-drug interaction.

TABLE 2: SOME OF THE PHARMACOKINETICS SOFTWARE WORKS IN FOLLOWING WAYS LIKES

CONCLUSION: Biobatch is very important in Drug Discovery and Regulatory Application for IND, NDA Approval. It is also very important after getting approval for future scale up and Post approval changes and as a substitute for studies by establishing IVIVC correlations. Biobatch quality are most important for drug discovery and drug design. Biobatch stability data and validation documentation is also important for audit purpose and product uniformity. Use of IVIVV and pharmacokinetic software is also helpful in clinical trial batch selection and decrease in the the clinical trial rejection. It also very important for faster FDA Review process by applying DOE and QbD approach for manufacturing Biobatch.

ACKNOWLEDGEMENT: This article has an approval for the publication from the Institute of Life Sciences, Ahmedabad University (No. 29). The authors thank the Director, Prof. Alok Dhawan, and Prof. Rishi Shanker Institute of Life Sciences, Ahmedabad University for not only the approval but also the support and encouragement with appreciation for the preparation of this article.

CONFLICT OF INTEREST: Nil

REFERENCES:

1. Paleshnuik L: Bio Batch considerations for Quality Assessment, Quality Workshop by World Health Organization. January 2012. http://apps.who.int/prequal/ trainingresources/pq_pres/4_PQ_AssessmentTraining/32%20Biobatch%20considerations%20for%20quality.ppt.Accessed on 110513.
2. Guidance for Industry, release solid oral dosage form scale-up and post approval changes: chemistry, manufacturing, and controls, in-vitro dissolution testing, and in-vivo bioequivalence, documentation-Center for Drug Evaluation and Research (CDER), Nov 1995. http://www.fda.gov/downloads/Drugs/Guidances/UCM070636.pdf: Accessed on 120513.
3. Waiver of in-vivo bioavailability and bioequivalence studies for immediate-release solid oral dosage forms based on a biopharmaceutics classification system, August 2000.http://www.fda.gov/downloads/Drugs/Guidances/ucm070246.pdf: Accessed on 210513.
4. Additional Guidance for Organization performing in Vivo Bioeqivalence Studies, Geneva- WHO, 2006 http://www. fda.gov/downloads/Drugs/Guidances/ucm070246.pdf: Accessed on 240513.
5. Guidance for Industry Bioavailability and Bioequivalence, Studies for Orally Administered Drug Products -General Considerations, March 2003 http://www.fda.gov/ downloads/Drugs/Guidances/ucm070246.pdf: Accessed on 250513.
6. 21 CFR 320.21, Sub Part B- Procedure for determining the Bioavailability or Bioequivalence of Drug Products, Requirements for submission of bioavailability and bioequivalencedata.http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=320.21: Accessed on 250513.
7. Shaikh M, Thirunagari B and Sathe A: The basic regulatory considerations and prospects for conducting bioavailability/bioequivalence (BA/BE) studies – an overview. Comparative Effectiveness Research 2011; 1: 1-25.
8. Matthew A and Spataro RP: Presentation on Pre Approval Inspections, New York District Office / WP-RP. http://www.asqlongisland.org/seminars/Preapproval_Inspections.pdf: Accessed on 260513.
9. Pranitha K and Gupta NV: Guide to inspections of tablet manufacturing facilities including pre/post approval issues as per USFDA. International Journal of PharmTech Research 2012; 4(1): 49-55.
10. International Conference on Harmonisation Steering Committee. Pharmaceutical Development Q8; Draft Consensus Guideline, Released for Consultation at Step 2 of the ICH Process; International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use, 18 November 2004. http://www.ich.org/fileadmin/Public_Web_Site/ICH_Products/Guidelines/Quality/Q8_R1/Step4/Q8_R2_Guideline.pdf: Accessed on 260513.
11. Guidance for industry, extended release oral dosage forms: development, evaluation, and application of in-vitro / in-vivo correlations http://www.fda.gov/ downloads/Drugs/GuidanceComplianceRegulatoryInformation/Guidances/ucm070239.pdf : Accessed on 211213.
12. Guidance for Industry ANDAs: Stability Testing of Drug Substances and Products, Question and Answers-Draft Guidance,August2013.http://www.fda.gov/downloads/Drugs/GuidanceComplianceRegulatoryInformation/Guidances/UCM366082.pdf Accessed on 010214
13. Guidance for Industry Q1 A(R2) Stability Testing of New Drug Substance and Products http://www.fda.gov/ downloads/regulatoryinformation/guidances/ucm128204.pdf Accessed on 010214
14. Qureshi SA: In-vitro – in-vivo correlation (IVIVC) and determining drug concentrations in blood from dissolution testing – a simple and practical approach. The Open Drug Delivery Journal 2010; 4: 38-47.
15. Niazi SK: Handbook of Pharmaceutical Manufacturing Formulations liquid products: Edition 2, 2009; 3: 41-42.
16. Murtaza G, Azhar S, Khalid A, Nasir, Ubaid M, Shahzad MK, Saqib F, Afzal I, Noreen S, Tariq M, Chohan TA and Malik A: Development of in vitro- in vivo correlation for pharmacokinetic simulation. African Journal of Pharmacy and Pharmacology 2012; 6(4): 257-63.
17. Emami J: In-vitro – in-vivo correlation: from theory to applications. Journal of Pharma Pharmaceutics Sciences 2006; 9(2): 169-89.
18. Sakore S, Chakraborty B: In-vivo – in-vitro correlation: a strategic tool in drug development. Journal of Bioequivalance and Bioavailability 2011; S3: 1-12.
19. Blume HH, Mc Gilveray IJ and Midha KK: Conference Report Bio international’ 94 Conferences on Bioavailability, Bioequivalence and Pharmacokinetic Studies Pre-Conference Satellite on In-Vivo/In-Vitro Correlation. European Journal of Drug metabolism and Pharmacokinetics 1995; 20(1): 9-13.
20. “Guideline for Industry: Stability Testing of New Drug Substances and Document. Products,” U.S. Department of Health and Human Services, Food and Drug Administration, September 1994. http://www.fda.gov/ RegulatoryInformation/Guidances/ucm128179.htm Accessed on 250214
21. Lieberman HA, Lachman L and Schwartz JB: Pharmaceutical Dosage Form: Tablets.Marcel Dekker Inc, New York Edition 2, Vol. 2, 1990.
22. Wachter AH: Validation of Pharmaceutical processes, Marcel Dekker Ic, New York, Edition 3, 2003.
23. Jambherkar SS and Breen PJ: Basic Pharmacokinetics. Pharmaceutical Press, London, United Kingdom 2009; 63(1): 55.
24. Chowdhury A, Islam S: In-vitro – in-vivo correlation as a surrogate for bioequivalence testing: the current state of play. Asian journal of Pharmaceutical Sciences 2011; 6(3-4): 176-90.
25. Shohin IE, Ramenskaya GV and Savchenko AY: Developing In Vitro-In Vivo correlation for Trimetazidine, Indapamide and Ciprofloxacin extendedrelease solid oral dosage forms. International Journal of Pharma and Bio Sciences 2011; 2(4): 573-80.
26. Cardot J M, Beyssac E and Alric M: In vitro–in vivo correlation: importance of dissolution in IVIVC. Dissolution Technologies 2007; 15- 19.
27. Nonsterile semisolid dosage forms scale-up and post approval changes: chemistry, manufacturing, and controls; in-vitro release testing and in-vivo bioequivalence documentation; guidance for industry; U.S. Department of Health and Human Services, Food and Drug Administration, Centre for Drug Evaluation and Research (CDER),U.S. Government Printing Office: Washington, DC, May 1997. http://www.fda.gov/downloads/ Drugs/Guidances/UCM070930.pdf : Accessed on 250214,
28. Note for Guidance on Development Pharmaceutics; European Agency for the Evaluation of Medicinal Products, Human Medicines Evaluation Unit, Committee for Proprietary Medicinal Products, CPMP/QWP/155/96; London, U.K., January 1998. http://www.ema. europa.eu/docs/en_GB/document_library/Scientific_guideline/2009/09/WC500003533.pdf : Accessed on 250214.
29. Gupta A, Mishra A, Gupta V, Bansal P, Singh R and Singh A: Recent trends of fast dissolving tablet - an overview of formulation technology. International Journal of Pharmaceutical & Biological Archives 2010; 1(1): 1-10.
30. Maddineni S, Chandu B, Ravilla S and Nama S: Dissolution research -a predictive tool for conventional and novel dosage forms. Asian Journal of Pharmacy and Life Science 2012; 2(1): 119-34.
    

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    How to cite this article:

    Bhatt JA and Goyal RK: Significance of pharmaceutical factors on selection of biobatch. Int J Pharm Sci & Res 2014; 5(11): 4635-43. doi: 10.13040/IJPSR.0975-8232.5(11).4635-43.

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