Manufacture of lyophilised injectable presentation for intramuscular administration in commercial swine herds begins with the combined live vaccine API being extracted from cryogenic storage at -70°C and tempered to 2–4°C in a Grade C cold room conforming to ISO 14644-1:2015 Class 7. The API concentrate is transferred to a jacketed 50 L stainless steel vessel fitted with a bottom-mounted magnetically coupled impeller. A stabiliser solution composed of 5.0% w/v sucrose, 2.0% w/v gelatin hydrolysate, 0.5% w/v NZ amine and 0.01 M phosphate buffer at pH 7.2 is added at a ratio of 1:4 API concentrate to stabiliser. Blending is maintained at 150 rpm for 45 min with the jacket held at 4°C. The final bulk is not passed through a sterilising-grade filter because the live bacterial fraction would be retained; the stabiliser solution is pre-filtered through a 0.22 μm sterilising membrane and all downstream transfers are performed under Grade A unidirectional airflow.

Fill volume is 2.0 mL per 5 mL Type I borosilicate glass vial conforming to Ph. Eur. 3.2.1, with chlorobutyl rubber stopper having moisture vapour transmission rate not more than 0.01 g/day. Filling uses a rotary piston pump with fill accuracy of ±1.0% and no recirculation of live vaccine bulk. Lyophilisation follows a freezing ramp from 4°C to -45°C at 0.5°C/min, held for 4 h; primary drying is run at shelf temperature -10°C and chamber pressure 90 μbar for 18 h; secondary drying is run at 25°C and 50 μbar until residual moisture by Karl Fischer, Ph. Eur. 2.5.12, is ≤3.0% w/w. Stoppering occurs under vacuum and vials are sealed with flip-off aluminium caps in an ISO 7/ISO 8 transition tunnel. Release specification includes sterility, Ph. Eur. 2.6.1, bacterial endotoxins, Ph. Eur. 2.6.14, virus titration and identity for the three antigen fractions. One reconstituted dose contains live classical swine fever virus C-strain at not less than 10^4.5 TCID50, Erysipelothrix rhusiopathiae serovar 2 at not less than 10^7.2 CFU, and Pasteurella multocida capsular type A at not less than 10^8.0 CFU; titre values are established by the marketing authorisation and validated against national reference standards. Terminal product type is a 1-dose lyophilised plug for reconstitution in 2.0 mL sterile diluent and intramuscular injection in pigs.

What buffer and carrier parameters govern drinking-water administration of the live trivalent powder?

Because oral drinking-water presentations bypass the sterile injection route, the dominant process conflict shifts from aseptic filling to reconstitution stability in chlorinated or acidic water lines. A terminal powder for drinking-water use is prepared from the same freeze-dried live trivalent vaccine API, milled under nitrogen at ≤20°C to a particle size D90 ≤125 μm, measured by Ph. Eur. 2.9.12. The milled API is blended in a 200 L V-blender at 10 rpm for 15 min with a carrier consisting of 4.0% w/w trehalose dihydrate, 0.5% w/w potassium dihydrogen phosphate, 0.2% w/w sodium glutamate and the remainder lactose monohydrate. Blend ratio is 1:9 API-to-carrier; the finished powder is released at 1.0 × 10^7 TCID50/g for the classical swine fever virus fraction with corresponding bacterial CFU per gram, and fill weight is 100 g per sachet.

Production is conducted at 18–22°C and ≤20% RH. Sachets are multilayer polyethylene terephthalate / aluminium foil / low-density polyethylene with oxygen transmission rate ≤1.0 cm³/m²/24 h and integrated silica gel desiccant. At administration, 10 g of powder is reconstituted in 100 L of drinking water after water withholding for 2 h, providing 1 dose per litre; the treated water volume is calculated for 2 h consumption. Water should have pH 5.5–7.5, free chlorine ≤0.1 ppm, and iron ≤0.05 mg/L; addition of 0.1% w/v sodium thiosulfate is used where chlorine removal is confirmed by amperometric measurement. Terminal product type is a water-dispersible oral vaccination powder for pigs supplied in 100 g and 1000 g laminated sachets.

Within dry-feed mass vaccination programmes for grower-finisher units, the granulated premix presentation is produced by low-shear tumble granulation to avoid thermal destruction of the temperature-sensitive classical swine fever virus fraction. Freeze-dried combined live vaccine API is blended with pre-gelatinised maize starch and microcrystalline cellulose in a 300 L double-cone blender at 8 rpm for 10 min. The binder solution, consisting of 2.0% w/v povidone K30 and 3.0% w/v trehalose dihydrate in purified water at 4–8°C, is sprayed at 15 g/min/kg of powder bed. Granulation is performed at product temperature 12–18°C; the wet mass is dried in a vacuum shelf dryer at 25°C and 30 mbar until residual moisture is 1.5–2.5% w/w. The dried granules are sieved to 250–850 μm. API loading is 10 g of freeze-dried concentrate per 1 kg premix; the premix is then diluted 1:1000 into finished dry feed so that each 1 kg of feed contains one oral dose.

Compliance for this presentation is anchored to Ph. Eur. 2.9.38 for particle size distribution, Ph. Eur. 2.5.12 for moisture, and the manufacturer’s live vaccine master seed release panel under Regulation (EU) 2019/6. Terminal product type is a vacuum-sealed aluminium foil bag of 500 g or 1 kg granulated oral premix for topdressing or non-pelleted meal feed. The granules must not be incorporated into pelleted feed conditioned above 50°C because dwell above 55°C can reduce the classical swine fever virus titre by more than 0.5 log10 TCID50; post-pelleting spray application is the only acceptable route when pelleted feed is unavoidable.

When the freeze-dried matrix is compressed into an oral tablet for feral pig bait stations

Direct compression of a live trivalent vaccine API into oral tablets is constrained by the same water activity thresholds as lyophilised parenterals but adds mechanical shear stress and die-wall friction to the degradation risk profile. The formulation for a 500 mg oral tablet is: 1.0% w/w lyophilised combined vaccine API, 48.75% w/w microcrystalline cellulose PH-102, 48.75% w/w mannitol, 1.0% w/w sodium starch glycolate, and 0.5% w/w magnesium stearate. Blending is performed in a 100 L tumble blender at 12 rpm for 8 min without pre-blending magnesium stearate beyond 2 min to avoid over-lubrication. Compression uses a 12-station rotary tablet press fitted with 11.0 mm flat-faced bevelled tooling, pre-compression force 1.5 kN, main compression force 4–6 kN, and press speed 20 rpm. Ejection force is monitored with rejection limit set at ≥800 N.

Under these conditions, tablet hardness is 60–80 N, friability not more than 0.8% w/w, measured by Ph. Eur. 2.9.7, disintegration time not more than 15 min in water at 37°C, measured by Ph. Eur. 2.9.1, and mass uniformity conforms to Ph. Eur. 2.9.5. The immediate-release matrix is not enteric coated because the target oral dose requires release in the oropharyngeal and gastric compartments; however, a thin hydroxypropyl methylcellulose film coat applied in a pan coater at 30°C inlet air and ≤20% RH may be used to reduce friability during bait-station handling. Terminal product type is a 500 mg oral tablet supplied in 10-tablet PVC/PVDC blister strips for incorporation into wild boar bait stations. Published data for direct compression of this specific trivalent live vaccine under GMP conditions is limited; each compression run therefore requires titre verification at the beginning, middle and end of the batch to define the mechanical loss envelope.

Hard-capsule oral baits in ring vaccination and emergency disease control

Ring vaccination against classical swine fever in feral pig populations has driven development of oral capsule presentation where the freeze-dried API can be concealed in a temperature-protected matrix inside a size 2 hard hydroxypropyl methylcellulose capsule. The API concentrate is first equilibrated to 2–8°C and then diluted 1:1 w/w with pre-chilled microcrystalline cellulose, mixed in a 50 L bin blender at 10 rpm for 12 min. Encapsulation is performed on a dosator-type capsule filler at 30,000 capsules/h with nitrogen purge and room relative humidity ≤18%. Fill weight is 250 mg, equivalent to one oral dose per capsule; fill weight variability acceptance is ±3.0%.

The filled capsules are dedusted, metal-checked, and immediately sealed into high-barrier aluminium foil pouches with desiccant; the terminal product type is a 250 mg oral capsule for feral pig baiting, supplied in 100-capsule foil pouches. Compliance anchors include Ph. Eur. 2.9.40 for uniformity of dosage units and Ph. Eur. 5.1.4 for microbiological quality of non-sterile oral dosage forms, supplemented by target animal safety requirements under Regulation (EU) 2019/6. Capsules should not be exposed to ambient temperatures above 25°C for more than 2 h during bait placement; direct sunlight and free-water contact are excluded by bait station design.

Because liquid ready-to-use presentations demand a narrower cold-chain envelope than lyophilised powders, downstream compounding into a stabilised oral solution is restricted to operations with verified 2–8°C distribution and a maximum hold time of 72 h after reconstitution. The lyophilised API is dissolved in a stabiliser buffer containing 5.0% w/v sucrose, 1.0% w/v gelatin hydrolysate, 0.2% w/v sodium chloride and 0.01 M phosphate buffer at pH 7.0. The reconstitution ratio is 1:20 API-to-diluent; each 1.0 mL of final solution provides one oral dose. Mixing is performed in a closed stainless steel vessel with impeller speed 120 rpm for 20 min at 4°C, and the solution is transferred to 50 mL low-density polyethylene sachets through a 0.45 μm prefilter; the final solution is not sterilising-filtered.

The solution must be used within 72 h and stored at 2–8°C; pH drift beyond 6.5–7.5 or exposure to temperatures above 10°C for more than 4 h invalidates the batch. Compliance is anchored to Ph. Eur. 2.9.19 for particulate contamination, Ph. Eur. 2.5.12 for moisture of the precursor plug, and the manufacturer’s live bacterial count specifications under national veterinary biologics release panels. Terminal product type is a ready-to-use oral liquid vaccine solution in 50 mL sachets for swine herd administration via liquid feed systems.