This presentation gives an overview into how advanced techniques such as manometric temperature measurement (MTM) and ice nucleation control can be used to enhance understanding of the freeze drying of your product, and provide additional control of its behaviour throughout the freeze drying cycle. This presentation was originally presented at Emerging Technologies in Freeze Drying, Stirling, 3rd April 2012.

1. Emerging Technologies in Freeze Drying
Stirling Innovation Park - 3rd April 2012
Enhanced Process / Product Understanding and
Control in Freeze Drying by using Manometric
Temperature Measurement (MTM) and
Nucleation Control
Dr. Margit Gieseler
Friedrich-Bergius-Ring 15 E-Mail: info@gilyos.com
D-97076 Würzburg Web: www.gilyos.com

2. The Freezing Drying Process
General Introduction
 Freeze Drying Phases - Overview
 Freezing phase:
• Principal dehydration step 3 - 6 hrs
• Separation of most of the solvent
hrs - days
(typically water) from the solutes to form ice
 Primary drying phase:
3 - 10 hrs
• Ice sublimation
• Longest phase  optimization of great
economical impact!
 Secondary drying phase:
• Removal of unfrozen water by diffusion and desorption
 Optimization
 Over the last years/decades: optimization efforts focused on primary drying phase.
 A truly optimized cycle includes all phases of the freeze drying process!
 Primary drying: run process close to / at / above critical formulation temperature,
tool: Manometric Temperature Measurement (MTM), Lyostar (SMART) freeze
dryer.
 Freezing phase: nucleation control, tool: ControLyo.
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3. Primary Drying
The Concept of MTM and SMART Freeze Dryer, 1
 The “MTM Procedure”: 3-7
 Isolate chamber from condenser for a short period of time (25 sec).
 Monitor pressure rise, collect pressure rise data (10 points/sec).
 Fit raw data to a pressure rise model function derived from heat and mass transfer
theory (MTM equation) by non-linear regression analysis.
 Calculate data for the vapor pressure of ice at the sublimation interface (Pice) and
dry product layer and stopper resistance (Rp+Rs).
 Use fundamental steady state heat and mass transfer equations to calculate (from
Pice and Rp data) additional parameters required to optimize the process.
  3.461 N  Ap  Ts     0.114 
P(t)  Pice  (Pice  P0)  exp 
 V  Rp  Rs    t  0.0465 Pice  T  1 0.811 exp   t   X  t
      Lice 
T 
24.7  Lice  Pice  P0 /Rp  Rs  0.0102 Lice  Ts  Tp
1  0.0102 Lice
Pice: pressure of ice, Torr (fit) Po: chamber pressure, Torr (set)
Rp+Rs: product resistance, cm² Torr h / g (fit) Ap: inner area of vials, cm² (known)
TS: shelf temperature, K (set) V: chamber volume, L (known)
N: number of vials (known) X: parameter for linear increase (fit)
Lice: ice thickness, cm (calculated) t: time of pressure rise (known)
∆T: product temperature difference, sublimation surface ↔ bottom of the vial (calc.)
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4. Primary Drying
The Concept of MTM and SMART Freeze Dryer, 2
 The SMART  Freeze Dryer
 LyoStar platform (SP Scientific).
 Expert system:
• Selection of optimum freezing procedure (crystalline / amorphous material)
• Automatic determination of target product temperature
• Selection of optimum chamber pressure (based on target product temperature)
• Dynamic adjustment of shelf temperature in primary drying based on MTM feedback
loop
 Input Parameters (among others):
• Number and type of product vials
• Inner vial cross-sectional area
• Fill weight / fill volume / density of solute
• Concentration of solution
• Nature of drug product
• Critical formulation temperature (Tc, Teu, Tg′)
 Auto-MTM: user pre-defined recipe, conduction and recording of MTM
measurements, no automatic adjustment.
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5. Primary Drying
SMART Freeze Drying Cycle, Example
75 mg/mL sucrose, uncontrolled nucleation, 5 cc tubing vials, 2.5 mL fill volume
[Staertzel P, Gieseler M, Gieseler H, unpublished data , 2012]
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6. Primary Drying
Product Resistance
12
TYPE 4
Product Resistance, Rp (cm Torr hr / g)
11
10
9
2
8
TYPE 3
7
l = dry layer thickness
6
5 RP (0) = resistance at l = 0
4 TYPE 2 A1, A2 = constants
3 TYPE 1
2
1
0
0.0 0.1 0.2 0.3 0.4 0.5 0.6
(13)
Dry Layer Thickness, l (cm)
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7. The Freezing Phase
Nucleation and Freezing
 Nucleation
 Nucleation = start of ice crystal formation.
 Nucleation does not start at the thermodynamic freezing point (Tf) but at a
temperature Tn , lower than Tf.
 RANDOM event!! freezing point Tf
 Freezing
 Freezing of pure ice.
 Concentration of all dissolved
Temperature [°C]
Components ↑. Tn
nucleation temp. Tn
 Crystallization at Teu (crystalline
systems). shelf temperature
shelf temperature
 Solidification at Tg′ (amorphous
systems).
Time [min] (9), modified
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8. The Freezing Phase
Impact on Product Morphology and Cake Appearance
 Super-Cooling
 Degree of super-cooling (Tn - Tf) determines ice crystal size:
Low Tn High Tn
• High Rp • Low Rp
• Long primary drying time • Short primary drying time
• Short secondary drying • Long secondary drying
time time
(10)
 Biggest obstacle in scale-up!
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9. The Freezing Phase
Controlling Nucleation - ControLyo, Praxair, 1
 Concept 11,12
 Cool product vials to desired nucleation temperature below the equilibrium freezing
point (e.g. -5°C); equilibrate product.
 Pressurize product chamber with argon (or nitrogen) gas to approximately 26 - 28
psig (ca. 1340 - 1450 Torr); equilibrate product.
 Depressurize the chamber to approximately 2 psig (ca. 100 Torr) in less than 3 sec
to induce nucleation.
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10. The Freezing Phase
Controlling Nucleation - ControLyo, Praxair, 2
Page 10

11. The Freezing Phase
Controlling Nucleation - ControLyo, Praxair, 3
 Controlled vs. Uncontrolled Nucleation
75 mg/mL sucrose, 5 mL vials, 2.5 mL fill, uncontrolled nucleation 75 mg/mL sucrose, 5 mL vials, 2.5 mL fill, controlled nucleation @ -3°C
[Staertzel P, Gieseler M, Gieseler H, unpublished data , 2012]
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12. SMART and ControLyo
Study Design
 SMART Cycle Uncontrolled
 Freezing / Thermal Treatment: 0.5°C/min to -40°C
 Primary Drying: SMART
 Annealing
 Freezing / Thermal Treatment: 0.5°C/min to -40°C + 6 h annealing @ -15°C
 Primary Drying: Auto-MTM, same settings as in SMART cycle uncontrolled
 ControLyo @ -8°C and @ -3°C
 Freezing / Thermal Treatment: nucleation at -8°C or -3°C, respectively, 0.5°C/min to
-40°C after nucleation
 Primary Drying: Auto-MTM, same settings as in SMART cycle uncontrolled
 SMART Cycle Controlled @ -3°C
 Freezing / Thermal Treatment: nucleation at -3°C, 0.5°C/min to -40°C after nucleation
 Primary Drying: SMART
 Secondary Drying Conditions
 ALL cycles: 0.1°C/min to 40°C, hold 360 min
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13. SMART and ControLyo
Obtained Primary Drying Recipes
Phase Step
Primary Secondary
Drying Step 1 2 3 17
Shelf Temperature SP [°C]
uncontrolled -37.0 -20.9 -24.4 40.0
controlled -37.0 -20.7 -17.1 40.0
Ramp Time [min]
uncontrolled 6 32 7 644
controlled 6 33 7 571
Hold Time [min]
uncontrolled 90 391 2497 360
controlled 90 90 1775 360
Vacuum SP [mTorr] 57 57 57 57
[Staertzel P, Gieseler M, Gieseler H, unpublished data , 2012]
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14. SMART and ControLyo
Process / Primary Drying Time, 1
Pirani/CM Differential [mTorr] 40
20
SMART, Uncontr.
Annealing
ControLyo@-3°C
ControLyo@-8°C
SMART+ControLyo@-3°C
2 mTorr
0
0 5 10 15 20 25 30 35 40 45 50 55 60
[Staertzel P, Gieseler M, Gieseler H, unpublished data , 2012]
1°Drying Time [hrs]
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15. SMART and ControLyo
Process / Primary Drying Time, 2
Primary Total Process Saving Saving Total
Drying Time Time Primary Process
[hrs] [hrs ] Drying Time* Time* [%]
[%]
SMART uncontrolled 49.5 72.7 0 0
Auto-MTM ControLyo @ -3°C 41.9 68.1 15.3 6.3
Auto-MTM ControLyo @ -8°C 44.6 70.2 10.0 3.5
Annealing 44.7 81.2 9.7 -11.7
SMART ControLyo @ -3°C 33.1 56.8 33.2 21.8
* compared to SMART uncontrolled [Staertzel P, Gieseler M, Gieseler H, unpublished data , 2012]
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16. SMART and ControLyo
TP-MTM / Rp
6 -35
-36
5
-37
-38
Rp [cm2*Torr*hr/g]
4
Temperature [°C]
-39
3 -40
SMART, Uncontr._Rp
Annealing_Rp
ControLyo@-3°C_Rp -41
2 ControLyo@-8°C_Rp
ControLyo+SMART_Rp
SMART, Uncontr._Tp-MTM -42
Annealing_Tp-MTM
ControLyo@-3°C_Tp-MTM
-43
1 ControLyo@-8°C_Tp-MTM
ControLyo+SMART_Tp-MTM
-44
0 10 20 30
Primary Drying Time [hrs] [Staertzel P, Gieseler M, Gieseler H, unpublished data , 2012]
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17. SMART and ControLyo
Product Appearance and Morphology
Uncontrolled nucleation
Uncontrolled nucleation ControLyo @ -3°C ControLyo @ -8°C
+ Annealing
200 µm 200 µm 200 µm 200 µm
[Staertzel P, Gieseler M, Gieseler H, unpublished data , 2012]
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18. SMART and ControLyo
Water Content
[Staertzel P, Gieseler M, Gieseler H, unpublished data , 2012]
Karl Fischer Titration, oven method, n=4
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19. SMART and ControLyo
Summary and Conclusion
 The freezing phase is an important part of the freeze drying cycle. The degree
of super-cooling determines ice crystal size and hence cake morphology and
drying performance (primary and secondary drying).
 Nucleation is a random process which can now be controlled, facilitating
batch homogeneity and easier scale-up.
 ControLyo in combination with MTM technology (SMART), an established
tool to optimize freeze drying cycles during the first run, can provide useful
information about the correlation of freezing regimen / pore size and drying
performance.
 A 33% saving of primary drying time could be achieved for 75 mg/mL sucrose
by combination of ControLyo and SMART.
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20. Literature
(1) Wang DQ. 2000. Lyophilization and development of solid protein pharmaceuticals. Int. J. of Pharmaceutics 203 (2000).
(2) Pikal MJ. 2002. „ Freeze Drying”. In: Encyclopedia of Pharmaceutical Technology, Marcel Dekker, New York.
(3) Milton N, Pikal MJ, Roy ML, Nail SL. 1997. Evaluation of Manometric Temperature Measurement as a Method of Monitoring
Product Temperature During Lyophilization. PDA J. Pharm. Sci. Technol. 51(1), 7-16.
(4) Tang X, Nail SL, Pikal MJ. 2005. Freeze-Drying Process Design by Manometric Temperature Measurement: Design of a Smart
Freeze-Dryer. Pharm. Res. 22(4), 685-700.
(5) Tang X, Nail SL, Pikal MJ. 2006. Evaluation of Manometric Temperature Measurement, a Process Analytical Technology Tool for
Freeze-Drying: Part I, Product Temperature Measurement. Pharm Sci Tech, 7 (1) Art. 14.
(6) Tang XC, Nail SL, Pikal MJ. 2006. Evaluation of Manometric Temperature Measurement, a Process Analytical Technology Tool
for Freeze-drying: Part II Measurement of Dry-layer Resistance. AAPS PharmSci-Tech, 7 (4) Art. 93.
(7) Tang XC, Nail SL, Pikal MJ. 2006. Evaluation of Manometric Temperature Measurement (MTM), a Process Analytical
Technology Tool in Freeze-Drying, Part III: Heat and Mass Transfer Measurement. AAPS Pharm SciTech, 7 (4) Art. 97.
(8) Tang X, Pikal MJ. 2004. Design of Freeze-Drying Processes for Pharmaceuticals: Practical Advice. Pharm. Res. 21(2):191-200.
(9) Searles et al. The Ice Nucleation Temperature Determines the Primary Drying Rate of Lyophilization for Samples Frozen on a
Temperature-controlled Shelf. J. Pharm. Sci., 90:860-871, 2001.
(10) Shon, M., The Importance of Controlling Nucleation Temperature During the Freeze Step, Introduction of ControLyo™
Nucleation on Demand Technology on the New FTS/SP Scientific™ LyoStar™3 Freeze Dryer, SP Scientific 2011
(11) Konstantinidis A, Kuu W, Otten L, Nail SL, Siever RR. 2011. Controlled Nucleation in Freeze-Drying: Effects on Pore Size in
Dried Product Layer, Mass Transfer Resistance, and Primary Drying Rate. J. Pharm. Sci., early view.
(12) Sever, R. 2010. Controlling Nucleation in Lyophilization: Effects on Process and Product. Proc. CPPR Freeze-Drying of Pharma-
ceuticals and Biologicals Conference. Garmisch-Partenkirchen, October 2010.
(13) Pikal, MJ. 1985. Use of Laboratory Data in Freeze Drying Process Design: Heat and Mass Transfer Coefficients and the
Computer Simulation of Freeze Drying. J. Parenter. Sci. Technol.: 33 (3) May-June, 115-138.
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