Double Rotary Tablet Press Requalification / Periodic Review Strategy

Understanding Double Rotary Tablet Presses: Role and Intended Use

The double rotary tablet press is a critical piece of equipment in oral solid dosage (OSD) manufacturing, specifically utilized to compress powder blends or granulated formulations into uniform tablets at high speeds. These machines are designed for continuous, high-throughput production environments, and are commonly employed in GMP facilities for the manufacture of tablets intended for human consumption. Their function lies at the heart of tablet manufacturing: dosing, compressing, and ejecting tablets with reproducible quality attributes such as weight, hardness, and friability.

The intended use of a double rotary tablet press includes processing validated formulations under tightly controlled conditions to ensure pharmacopoeial compliance and patient safety. Boundaries for its intended use are confined to the compression of qualified product blends into tablets within defined specifications (e.g., size, shape, weight). Operation outside these boundaries—such as compressing unapproved blends, modifying mechanical settings outside validated ranges, or using non-qualified tooling—falls outside validated conditions and is not considered GMP-compliant.

Scope of Double Rotary Tablet Press Requalification

A robust requalification or periodic review strategy for a double rotary tablet press encompasses a clear definition of what is included and excluded in the scope:

• In Scope:
  • Mechanical, electrical, and control system health checks
  • Verification of critical operating parameters (compression force, turret speed, feeding mechanisms)
  • Review of alarms, interlocks and safety mechanisms
  • Confirmation of cleaning and changeover procedures (product contact surfaces)
  • Assessment of core software functions (if integrated HMI/SCADA present)
  • Assessment of product contact change parts (punches, dies, feeders)
• Out of Scope:
  • Non-product-contact peripheral systems (e.g., external dust extraction units, unless integral)
  • Facility infrastructure and HVAC systems
  • Downstream packaging equipment (e.g., blistering, bottling lines)
  • Non-critical auxiliary software (data historian, non-control level systems)
  • Production batch record reviews (unless indicating equipment performance trend)

Criticality Assessment: Product and Patient Risks

Double rotary tablet presses are classified as highly critical equipment in the OSD process chain. Their role and design entail direct and pronounced risks that must be managed via requalification strategy:

• Product Quality Impact: Malfunction or drift in tablet press performance can lead to dose variability, improper hardness, or inconsistent tablet integrity—all of which directly influence product quality.
• Patient Safety Risk: Inadequate operation can result in incorrect API dosing, introducing under- or over-dosed medication to patients. Equipment faults also raise cross-contamination risk from previous products.
• Data Integrity Impact: Integrated electronic controls or batch reporting must provide secure, reliable, and review-ready records. Failure here threatens regulatory compliance and patient safety alike.
• Contamination and Mix-up Risk: Shared equipment must be fully cleaned and verified to avoid cross-product contamination or misidentification.
• Environment, Health, and Safety (EHS) Risk: Mechanical and electrical safety features (e.g., guards, emergency stops) are essential to protect operators from injury due to moving parts or powder exposure.

GMP Expectations for Double Rotary Tablet Presses

For this category of equipment, GMP principles require that the press is:

• Qualified to operate consistently within specified parameters over its lifecycle
• Routinely maintained, cleaned, and requalified per a defined schedule or after major changes/repairs
• Capable of robust segregation between product campaigns (via cleaning verification and change part records)
• Fitted with validated controls (e.g., compression force monitoring, turret speed limits, punch detection sensors)
• Protected with alarms/interlocks to prevent unsafe or non-compliant operation (e.g., door open/guard removal detection)
• Accompanied by comprehensive, traceable documentation (logbooks, calibration records, maintenance logs)
• Integrated in the facility’s overall contamination control and data integrity strategy

Designing a User Requirements Specification (URS) for Tablet Press Requalification

The User Requirements Specification (URS) is foundational in defining the requirements against which the double rotary tablet press will be (re)qualified. A URS for this equipment type should cover:

• Capacity and Throughput: Maximum tablet output per hour, range of tablet sizes and shapes
• Compliance and Safety: Required safety features and necessary GMP compliance elements
• Product Contact Materials: Specification of all surfaces in contact with product—material and finish
• Control System/Interface: Required process monitoring, alarms, and audit trail capabilities
• Cleaning/Changeover: Maximum allowable changeover time, accessibility for cleaning, cleaning validation requirements
• Maintenance and Calibration: Features supporting ease of maintenance, built-in calibration references if applicable

Example URS Excerpt:

• Maximum output capacity: 240,000 tablets/hour
• Tablet compression force adjustable from 5 to 100 kN, with digital display
• All product-contact parts: SS316L, Ra < 0.6 μm
• Integrated punch force monitoring & automatic reject on deviation
• HMI with 21 CFR Part 11 compliant audit trail
• Full-glove access to all product-contact areas for cleaning; validated cleaning method must achieve ≤10 ppm carryover
• Interlocked guards and emergency stops at all operator access points

Risk Assessment Foundations: FMEA-Style Considerations

The risk assessment underpinning qualification and ongoing requalification relies on structured tools such as Failure Modes and Effects Analysis (FMEA). Key principles include:

• Identifying failure modes in compression, feeding, and ejection systems (e.g., stuck punches, feeding jam, force drift)
• Assessing severity: e.g., API misdosing scores high severity due to patient risk
• Estimating occurrence likelihood based on maintenance records, service intervals, and component reliability
• Detectability: Are alarms, sensors, or operator checks present to detect failures quickly?
• Implementing controls: Automated in-process controls, operator training, procedural checks, and electronic batch records

Sample FMEA-Driven Table: Critical Requirements & Associated Controls

A data-driven, risk-based approach ensures that qualification requirements for double rotary tablet presses are commensurate with their criticality and potential impact on product quality, patient safety, and regulatory compliance.

The next sections continue the qualification storyline with practical tests, evidence expectations, and lifecycle controls appropriate for this equipment.

Supplier Controls for Double Rotary Tablet Press Requalification

Robust supplier controls are a foundational aspect of double rotary tablet press requalification in GMP environments. The vendor’s capability to consistently supply compliant equipment directly impacts product quality and regulatory compliance. Supplier qualification must go beyond a basic quality agreement and address the unique risks of oral solid dosage manufacturing.

• Vendor Qualification:
  • Conduct on-site or remote audits covering GMP systems, documentation practices, component traceability, and change management.
  • Verify supplier experience with regulated markets and history of supplying tablet presses to pharmaceutical clients.
  • Assess supplier’s internal calibration systems for critical measuring devices and adherence to international standards (e.g., ISO 9001).
• Document Package Review:
  • Detailed user, installation, and maintenance manuals; recommended spare parts lists.
  • Complete drawings—mechanical, electrical, pneumatic, and control schematics.
  • Validated cleaning protocols if any product-contact components require routine cleaning.
  • Functional description and control system overview (including pictorial workflows).
• Material Certificates:
  • Critical for all product-contact components (e.g., compression tooling, feed frames, hopper) using SS316L or pharma-grade engineering plastics.
  • Material traceability: certificate of conformity, raw material origin, and heat/lot numbers to be cross-referenced.
  • Surface finish certificates in line with hygienic design requirements (Ra < 0.8 µm if specified).
• Software Documentation (if applicable):
  • Software version traceability, validated backup/restore procedures, and cybersecurity controls.
  • 21 CFR Part 11 compliance declaration for data integrity (audit trail, controlled user access).
  • Software functional description and risk assessment summaries for any programmable logic controller (PLC) or Human-Machine Interface (HMI) systems.

FAT and SAT Strategy for Double Rotary Tablet Presses

The Factory Acceptance Test (FAT) and Site Acceptance Test (SAT) collectively ensure that the equipment performs as intended prior to and after installation. For double rotary tablet presses, FAT is generally conducted at the vendor’s facility. Key parameters include:

• What to Test:
  • Mechanical integrity: turret rotation, punch and die alignment, feeder systems, lubrication systems, and compression roller smoothness.
  • Safety features: interlocks, guards, emergency stops, and fail-safe behavior under simulated faults.
  • Basic controls: manual/automatic modes, HMI navigation, hardware alarms, and initial connectivity tests.
  • If agreed, preliminary compression of placebo material to demonstrate tablet output and ejection functions.
• Who Should Witness:
  • Purchaser’s process/validation engineers and QA representative.
  • Vendor’s engineering and quality assurance teams.
• Deviations Handling:
  • All discrepancies to be logged immediately. Categorize as critical, major, or minor (affecting GMP compliance, product quality, or recording only).
  • Corrective actions agreed and re-tested before shipment.
  • FAT report to include deviation log and final disposition (accept/withhold release).

At site, the SAT serves to re-confirm mechanical and control functions under site utility conditions. Scope should include:

• Verification of as-delivered condition (no transit damage, correct orientation, all accessories).
• Repeat of critical FAT steps, adapted to the actual environment (e.g., power quality, air supply, integration into data collection systems).
• Checklist-driven review for all punch/die sets, changeover tools, and operator safety systems.

Design Qualification (DQ) for Double Rotary Tablet Presses

Design Qualification is the documented verification that the proposed design meets the intended use and GMP requirements, particularly for oral solid dosage applications.

• Key Design Reviews:
  • Review of general arrangement and layout drawings for compliance with ergonomic, safety, and maintenance needs.
  • Assessment of product flow and ease of cleaning (minimizing dead leg and crevice formation).
  • Verification of dust containment features—extraction points, sealed covers, and options for wash-in-place or tool-free disassembly.
• Drawings:
  • Mechanical assembly, product-contact parts, safety guards, and panel layouts.
  • Schematic diagrams for power, signal, and pneumatic circuits.
• Materials of Construction:
  • Detailed list and certificates for all product contact parts; e.g., punches, dies, feed frame, hoppers—typically AISI 316L stainless steel or approved pharma-grade engineering plastics.
• Hygienic Design:
  • Smooth interior/exterior finishes with defined Ra values (typically <0.8 µm), angled surfaces to avoid powder retention, sanitary gaskets.
  • Design to prevent cross-contamination (easy access for cleaning, minimal product hold-up).
  • Drainage and cleaning validation documentation, if an automated cleaning system is present.

Installation Qualification Planning and Execution

The Installation Qualification (IQ) phase verifies that the double rotary tablet press and its associated systems are installed per the manufacturer’s recommendations and GMP requirements. This includes a rigorous, documented assessment of all components and services before operational testing.

• Installation Checks:
  • Mechanical anchoring, alignment checks, and stability.
  • All required sub-assemblies available and installed per as-built drawings.
  • System labeling for all utilities, flow direction, and emergency stops.
• Utilities Verification:
  • Confirm availability of compliant electrical supply (three-phase, power quality in line with OEM specs, e.g., ±10%).
  • Air supply: compressed air must meet ISO 8573-1 Class 1.4.1 or better for pneumatic actuation and dust control features.
  • Water systems (if applicable): Reverse Osmosis (RO) or Purified Water (PUW) for any inbuilt wash features, validated sources.
  • Steam: demonstrable connection to clean steam per EN 285, if required for cleaning or heating.
• Instrumentation and Calibration:
  • Initial calibration status of pressure, temperature, force, and rotation sensors; documented traceability for all calibration certificates.
  • Labels must indicate calibration status with due/expiry dates clearly visible.
• As-Built Documentation:
  • Compile a dossier including redlined drawings, wiring diagrams, utility connection records, and final “as installed” layouts mediated against DQ package.
• Safety Checks:
  • Verification of machine guards, interlocking, electrical earthing, and ESD controls.
  • Inspection of environmental compliance—dust extraction/containment verified against risk assessment.

Environmental and Utility Dependencies: Acceptance Criteria

Environmental and utility infrastructure directly impact the suitability of a double rotary tablet press for GMP production of oral solid dose products. Acceptance criteria for site conditions should be strictly defined in the qualification protocols:

• HVAC/cleanroom class: Confirm as per product grade (e.g., ISO 8 or Grade D for standard tablets). Temperature and humidity must be controlled within specified ranges (e.g., 18–25°C, 40–60% RH) to prevent powder bridging and ensure compressibility.
• Compressed air quality: ISO 8573(specific class) documented by latest site certificate, with dew point and particle count tests.
• Water: RO or PUW supply, regular microbiological and conductivity testing results, piping integrity within last 12 months.
• Steam (if used): Clean steam passing EN 285 sterility tests, free from particulates and non-condensable gases, with chemical test records.
• Power: Demonstrated voltage stability and phase balance during peak equipment load.

Supplier Package + DQ/IQ Checklist

The next sections continue the qualification storyline with practical tests, evidence expectations, and lifecycle controls appropriate for this equipment.

Operational Qualification (OQ) for Double Rotary Tablet Press: A Comprehensive Approach

The Operational Qualification (OQ) phase of double rotary tablet press requalification is a critical stage focused on verifying and documenting that the equipment operates according to its intended purpose across all defined operational ranges. This ensures ongoing process consistency, regulatory compliance, and patient safety. The specificity and complexity of double rotary tablet press operation — including high throughput, precision, and exposure to mechanical and automated controls — require meticulous OQ planning, execution, and documentation, with special attention to GMP and data integrity.

Key OQ Elements for Double Rotary Tablet Presses

• Functional Testing of Mechanical and Automated Systems
• Verification of operating ranges for all critical process parameters
• Alarms/interlocks functionality and setpoint verification
• Execution of challenge tests for critical failures or deviations
• Instrumentation checks and calibration verification
• Verification of electronic controls, data integrity, and GMP management systems
• Line clearance, status labeling, batch record linkages for traceability
• Safety and EHS feature verification (interlocks, emergency stops, guarding, exhaust systems)

Practical Execution of OQ: Steps and Acceptance Criteria

1. Functional Verification of Major Subsystems

All principal systems must be operated, and their performance measured against manufacturer and user requirements. This comprises:

• Main drive motor: Confirm operation at low and high speeds (e.g., 20 rpm to 80 rpm; typical range for product-specific settings).
• Feeder system: Test volume delivery, agitation, and proper flow at settings ranging from formula minimum to maximum.
• Compression stations: Measure upper and lower punch movement, pressure transducers, and ejection mechanisms.
• Tablet ejection mechanism: Visually inspect and measure ejection force (e.g., force remains within 20–35 N; value for reference).
• Automatic weight regulation: Simulate load changes and confirm quick detection and automatic correction within ±2%

For each system, acceptance criteria should be predefined with input from the equipment manual, site SOPs, and regulatory standards. For example:

• Consistent tablet output at each tested speed (±2% of target weight at all speeds tested)
• Accurate powder feed rates matching setpoint (±5g/h misalignment triggers alarm)
• Punch force sensors calibrated to read within ±1% FS (full scale)

2. Operating Ranges and Setpoint Verification

The double rotary tablet press must be challenged and verified across the complete range of qualified parameters, including:

• Press speed: e.g., operation validated at 20, 40, 60, and 80 rpm
• Main compression force: Test at 40 kN, 60 kN, and 80 kN (example values)
• Weight adjustment range: Check at upper and lower setpoints (e.g., 150 mg and 600 mg for tablet weight)
• Pre-compression settings: Confirm controls function and reach set values

Alarms must trigger at pre-defined deviations (e.g., punch pressures ±5% outside setpoint or weight drift >2% triggers stop/interlock).

3. Alarms, Interlocks, and Challenge Testing

To ensure safety and process integrity, simulated failures (challenge tests) are essential. Key verifications include:

• Emergency stop activation: Machine halts within 2 seconds (example value)
• Door/interlock sensors: Opening guard triggers immediate stop, alarm
• Overload simulation: Artificially induce motor or punch force overload to trigger cut-out and record event in audit trail/logbook
• Inadequate powder feed: System alarms within 10 seconds of low-flow detection

4. Instrumentation Calibration and Verification During OQ

Instrumentation associated with the press—such as pressure sensors, load cells, RPM tachometers, and electronic scales—must be confirmed to be within calibration status. This is typically documented by:

• Reviewing most recent calibration certificates (traceable to national/international standards)
• Performing verification checks (e.g., three-point calibration for scale; all within ±0.1% nominal)
• Comparing actual values versus programmed setpoints for all critical sensors

Any devices found out-of-calibration are to be tagged “Out of Service” and not used until recalibrated and verified.

5. Computerized Controls & Data Integrity in OQ

Most modern double rotary tablet presses incorporate automated PLC or SCADA-based controls with data acquisition and, often, direct integration with MES or batch record systems. Requalification OQ must critically assess:

• User role management: Access defined per SOP (e.g., only supervisors allowed to change recipe/setpoint; operators limited to start/stop).
• Audit trail: Changes are time-stamped, recorded, and reviewable for all critical parameters and events, including alarms and overrides.
• System time synchronization: System clocks validated against site standards (discrepancy <1 minute allowed).
• Data backup & restore: Test retrieval after simulated data loss; all recipe and batch data must be recoverable.
• Electronic signature functionality: If applicable, validate that e-signatures are unique and cannot be falsified.

Data review SOP must include periodic spot checking of audit trail completeness, user activity tracking, and confirmation that unauthorized changes are not possible.

6. GMP Controls: Line Clearance, Labeling, and Documentation

The OQ phase must demonstrate strict adherence to key GMP practices specific to the double rotary tablet press environment. These include:

• Line clearance verification: Visual and documented confirmation that no residual material, documentation, or tools from previous campaigns remain.
• Status labeling: All equipment must display clear, current status labels (e.g., ‘Under OQ’, ‘Clean’, ‘Not for Use’).
• Logbooks: OQ execution and system events are logged in bound logbooks; ensure logbook control, issuance, and review per procedure.
• Batch record integration: Any OQ impacting actual production must provide direct linkage/data for batch record documentation and review.

These controls ensure traceability of testing, results, and compliance during and after OQ.

7. Safety & Compliance Feature Checks

Double rotary tablet presses operate at high speeds and pressures, presenting safety risks if controls are inadequate. During requalification OQ, verify:

• Machine guarding: All physical guards are present, locked, and free from tampering; removal disables operation via interlock.
• Pressure relief devices: Simulate overpressure conditions (if permissible) to confirm pressure-relief functionality.
• Emergency stops: Each E-stop, including remote and local, brings machine to a safe state within 2–3 seconds (example value).
• Dust extraction/interlocks: Confirm dust collector interfaces and alarms; operation must not proceed if extraction not engaged.
• Electrical safety: Power isolation checks, emergency shutdown, safe grounding verified.

All safety signage, warnings, and lights must be checked for functionality and visibility under operational conditions.

Sample OQ Checklist: Double Rotary Tablet Press Requalification

Documentation and Review

All OQ results and data integrity checks during double rotary tablet press requalification must be documented in compliance with site documentation standards and regulatory guidance (e.g., FDA 21 CFR Part 11, Annex 11 for electronic records). Raw data, printed and electronic, logbooks, executed checklists, calibration records, and audit trails should be retained and readily retrievable for the required retention period. Deviations or out-of-specification results require documented investigation and corrective action as per CAPA processes. Only after successful OQ completion, with all acceptance criteria met and results reviewed/approved by Quality, should equipment proceed to next validation/production use.

The next sections continue the qualification storyline with practical tests, evidence expectations, and lifecycle controls appropriate for this equipment.

Performance Qualification (PQ) of Double Rotary Tablet Press

Performance Qualification (PQ) is a critical phase in the requalification lifecycle of a double rotary tablet press, designed to ensure that the press consistently produces tablets meeting all quality requirements under routine and stressed (worst-case) conditions. PQ not only validates the operational competencies of the equipment but also supports ongoing compliance with Good Manufacturing Practice (GMP) expectations for oral solid dosage form production.

Routine and Worst-Case Strategies

For double rotary tablet press requalification, PQ requires a comprehensive approach:

• Routine Production Runs: These simulate the standard manufacturing process, confirming consistent performance with the usual products and typical operating parameters.
• Worst-Case Scenarios: Challenges include operation at upper and lower specification limits for key variables (e.g., minimum/maximum tablet weight, variation in granule characteristics, highest punch speed). Selection of challenging product formulations (e.g., stickiest or driest blends) ensures a thorough evaluation.
• Multiple Batches and Changeovers: Execution of at least three consecutive successful batches demonstrates repeatability and reproducibility. For machines used in frequent product changeovers, PQ may include rapid sequence cleaning and startup to evaluate turnaround robustness.

PQ Sampling Plan, Repeatability, Reproducibility, and Acceptance Criteria

A robust sampling plan underpins PQ validity and confidence in the double rotary tablet press’ long-term reliability. Key activities involve in-process sampling across the entire batch and during different time points (start, midpoint, end). All critical quality attributes such as tablet weight, hardness, friability, thickness, and content uniformity are measured.

All results must document minimal batch-to-batch and within-batch variation. Deviations from acceptance criteria trigger investigation and, if systemic, may indicate the need for further requalification or process improvements.

Cleaning and Cross-Contamination Controls

As the double rotary tablet press operates through direct product contact, cleaning validation and verification are critical for both product integrity and patient safety. PQ integrates with cleaning validation by:

• Assessing cleaning efficacy through swab/rinse sampling immediately after product runs and changeovers.
• Verifying that cleaning SOPs are followed precisely during PQ and that residues of active ingredients, cleaning agents, and microbial contamination remain below pre-defined thresholds.
• Simulating worst-case scenarios (e.g., cleaning after highly potent or adhesive products) to demonstrate the equipment’s cleanability and the ongoing effectiveness of cleaning procedures.

PQ outcomes support ongoing cleaning verification schedules, and results are crucial to developing and revising cross-contamination control SOPs.

Continued Process Verification & Ongoing Qualification

After requalification, continued process verification (CPV) ensures the double rotary tablet press remains in a validated state throughout its operational lifecycle. This includes:

• Real-time monitoring of critical process parameters such as turret speed, compression force, and tablet weight.
• In-process quality checks and trending of product attributes to detect shifts or emerging trends.
• Scheduled review of cumulative process and quality data (periodic review), facilitating proactive identification of potential issues.

All process changes, upgrades, or major maintenance tasks require impact assessment through change control, with potential partial or full requalification as dictated by risk.

SOPs, Operator Training, Maintenance, Calibration, and Spares

A robust operational foundation complements equipment requalification:

• Standard Operating Procedures (SOPs): Must be current and specific to the double rotary tablet press, covering operation, cleaning, maintenance, troubleshooting, and safety.
• Training: Operators and maintenance personnel must be trained and assessed for competency, including periodic refresher programs and PQ requirements.
• Preventive Maintenance: Scheduled preventive maintenance (PM) plans aligned with the manufacturer’s recommendations and informed by PQ performance data. All critical spares should be readily accessible to minimize downtime and uncontrolled interventions.
• Calibration: All measurement systems (e.g., weight sensors, pressure gauges, hardness testers integrated with the tablet press) require up-to-date calibration; certificates should be traceable and routinely reviewed.

Change Control, Deviations, CAPA, and Requalification Triggers

Robust change control and quality management are vital. Typical triggers for requalification of a double rotary tablet press include:

• Major maintenance, repairs, or component replacement (e.g., turret, cam tracks, motor drive)
• Software changes (e.g., control system updates, recipe modifications)
• Recurring product non-conformances, adverse PQ/CPV trends, or cleaning failures
• After periods of extended inactivity or after a change in location of the press

Any deviations encountered during PQ or routine operation are fully investigated through the deviation/CAPA process. Corrective actions are tracked and must be closed prior to requalification completion. All such events inform the scope and depth of future requalification activities.

Validation Deliverables: Protocol and Report Structure

Double rotary tablet press requalification should always be documented in standardized, auditable deliverables:

• PQ Protocol: Outlines purpose, scope, responsibilities, detailed test plans, sampling and acceptance criteria, change control references, and risk assessments.
• Data & Results: Worksheets and raw data forms for operational, quality, and cleaning results.
• Summary Report: Interprets and summarizes all test outcomes, including deviations, CAPA resolutions, and final qualification status. Should provide a clear traceability matrix mapping protocol requirements to executed/testing data.
• Document Control: All documents (protocols, reports, forms) must be securely managed, version-controlled, and archived per GMP.

Traceability is crucial: each requirement or risk point in the protocol must be evidenced by specific test data or results in the summary report, supporting a transparent, auditable qualification history.

FAQ: Double Rotary Tablet Press Requalification

How often should a double rotary tablet press be requalified?

Typically, requalification is based on a risk-based periodic strategy (e.g., every 2–3 years) or upon major changes, maintenance events, or recurring quality issues. Regulatory guidance and company procedure will dictate the exact interval.

Does requalification always require a full PQ, or are targeted verifications sufficient?

If change impact is low (e.g., minor software updates), targeted PQ or verification may suffice. Major changes usually require full or extensive PQ. The scope should always be justified and documented by change control.

What documentation is needed for a successful requalification?

Key deliverables include the executed PQ protocol, raw data, completed test records, deviation/CAPA logs, and a comprehensive summary report with traceability to all requirements.

How does cleaning validation fit within requalification?

Cleaning effectiveness is directly tested during PQ as part of requalification, and evidence of validated cleaning (below residue and cross-contamination limits) is necessary. Any cleaning SOP changes require associated requalification or verification steps.

What happens if the equipment fails PQ tests during requalification?

All failures must be fully investigated via deviation/CAPA, with root cause determined and corrective actions implemented. PQ may be repeated, and equipment cannot return to GMP production until qualification is successful.

Are operators involved in PQ and requalification activities?

Yes, trained operators must execute or assist in test runs to ensure PQ reflects real routine practices and personnel variability is considered in reproducibility assessments.

How are calibration and preventive maintenance linked to requalification?

All calibrations and preventive maintenance must be current before PQ starts. Any overdue or failed calibration/maintenance is a requalification blocker and must be closed prior to test initiation.

Conclusion

Requalification of a double rotary tablet press is an exacting process integral to ongoing product quality and regulatory compliance in oral solid dosage manufacturing. It verifies, with documented evidence, that the press can consistently produce tablets to rigorous standards—across all intended operational scenarios and after any significant change or event. This assurance hinges on meticulous PQ execution, effective cleaning and maintenance controls, robust change management, and comprehensive documentation. Implemented properly, a strategic requalification approach not only satisfies regulatory expectations but also supports sustainable, high-quality operations and robust patient safety outcomes in every batch manufactured.