Two positive sterility tests, a leaking HEPA filter and 5,200 vials already sold
An injectable unit manufactures Ceftriaxone sodium 1 g powder for injection, batch CRN-118, comprising 9,400 vials. Release testing by membrane filtration shows turbidity in 2 of 20 vials: one in fluid thioglycollate medium incubated at 35 °C on day 5, and one in soyabean casein digest medium at 22 °C on day 9. Both grow a Gram-positive spore-forming rod identified as Bacillus cereus. The same organism, with an indistinguishable PFGE pattern, was recovered from a settle plate in the grade A filling zone on the same day and from an operator's glove. The last three media fills were satisfactory, but a later integrity test showed a leak in the HEPA filter of the filling station, and the room differential pressure log records two excursions below 10 Pa in the previous month. 5,200 vials have already been dispatched to three States. The QC head proposes to repeat the sterility test on 40 vials and release the batch if the repeat passes.
1. Should the sterility test be repeated, and could a passing retest justify release of this batch?
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The retest is not a route to release here.
Pharmacopoeial sterility testing allows a single repeat when growth appears in the first test, but that provision exists to rescue a test invalidated by laboratory error - a contaminated isolator, a faulty technique, a compromised negative control. It is not a mechanism for overriding a valid failure.
Apply that to the evidence.
- The contaminant is identified to species, not merely described as a spore-bearer.
- The same organism with an indistinguishable PFGE pattern was found on a grade A settle plate and on an operator's glove on the same day. That is a source link, not coincidence.
- The HEPA filter subsequently failed integrity testing, and differential pressure fell below 10 Pa twice in the month - a plausible physical route for particles and organisms into the critical zone.
The combination points to contamination during filling, i.e. the vials themselves are non-sterile. Where the root cause is in the process, a negative retest would only demonstrate that sampling from a heterogeneous population can miss contaminated units. Releasing on that basis is testing into compliance and is indefensible.
Correct conclusion. The batch fails the sterility requirement and is not of standard quality. The investigation should continue as an out-of-specification/deviation investigation, but the disposition is rejection, not retest-and-release. If a repeat is done at all, it is for information, with the result pre-committed as non-releasing.
2. Determine the disposition of the batch and the recall strategy, including classification and communications.
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Disposition. Reject and quarantine all remaining 4,200 vials; place them under 'rejected' status with restricted access; do not reprocess or re-sterilise a terminally non-sterile powder for injection.
Recall. 5,200 vials in three States must be recalled. Classify the recall on hazard:
- A parenteral product with confirmed viable bacterial contamination, given by injection to patients who may be immunocompromised, carries a real risk of sepsis and death. That places it at the top of the scale - a Class I recall, or at minimum Class II if the organism is judged unlikely to cause serious harm. Do not allow the firm to self-classify downward.
- Notify CDSCO and the three State licensing authorities promptly, with batch details, quantity, distribution list and the recall depth (up to retailer/hospital level).
- Issue a rapid alert and a public notice; write to the consignees to stop use and return stock; track recovery percentage against dispatched quantity and report it.
Clinical communication. Prescribers and hospital pharmacists should be told to watch for fever, rigors or unexplained deterioration in any patient who received the batch, and to report such events through PvPI.
Record-keeping. All recall correspondence, quantities recovered and destruction records form part of the case file and will be examined if the matter is prosecuted.
Do not wait for the repeat sterility result before initiating the recall; delay is itself a finding against the firm.
3. As the inspecting officer, what root-cause and compliance findings would you record, and what regulatory action would you recommend?
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Root cause. A defective HEPA filter in the filling station, plus repeated loss of differential pressure below 10 Pa, allowed environmental contamination of the grade A zone; the same organism on the operator's glove points to gowning and aseptic technique failure. Media fills passing earlier does not exclude this - media fill is a periodic challenge, not a continuous monitor, and the filter failed between runs.
Schedule M deficiencies to record.
- Filter integrity testing not performed at the required frequency or with change-out criteria.
- Differential pressure excursions recorded but not investigated or acted upon.
- Environmental monitoring trend not reviewed for the filling zone.
- Operator gowning qualification and glove disinfection not verified.
- Batch not held pending environmental review before release.
Regulatory action.
- Prohibit manufacture of sterile products from that filling line until corrective action is completed and validated by three consecutive successful media fills, filter integrity re-verification and an environmental monitoring trend review.
- Seize and seal records, monitoring logs, media fill records and the retained samples under the Inspector's powers.
- Recommend suspension of the manufacturing licence to the licensing authority pending investigation, and consider prosecution for manufacture of a not-of-standard-quality drug.
- Require a written CAPA with named owners and dates, and a re-inspection before the prohibition is lifted.
Reasoning. The finding is systemic, not a single bad vial; the remedy must therefore address the line and the quality system, not just the batch.