An implantable drug delivery system (IDDS) for refractory cancer pain provides sustained pain control, less drug-related toxicity, and possibly better survival compared with comprehensive medical management (CMM).

BACKGROUND: The randomized clinical trial of implantable drug delivery systems (IDDS) plus comprehensive medical management (CMM) versus CMM alone showed better clinical success at 4 weeks for IDDS patients. This 'as treated' analysis assessed if improvements in pain control, drug toxicity and survival were maintained over time. PATIENTS AND METHODS: We compared those who received IDDS with those who did not receive IDDS (non-IDDS). All patients had Visual Analogue Scores (VAS) for pain > or =5/10 on at least 200 mg morphine or equivalent daily. RESULTS: At 4 weeks, 46 of 52 (88.5%) IDDS patients achieved clinical success compared with 65 of 91 (71.4%; P=0.02) non-IDDS patients, and more often achieved > or =20% reduction in both pain VAS and toxicity [35 of 52 (67.3%) versus 33 of 91 patients (36.3%); P=0.0003]. By 12 weeks, 47 of 57 (82.5%) IDDS patients had clinical success compared with 35 of 45 (77.8%; P=0.55) non-IDDS patients, and more often had a > or =20% reduction in both pain VAS and toxicity [33 of 57 (57.9%) versus 15 of 45 patients (33.3%); P=0.01]. At 12 weeks the IDDS VAS pain scores decreased from 7.81 to 3.89 (47% reduction) compared with 7.21 to 4.53 for non-IDDS patients (42% reduction; P=0.23). The 12 week drug toxicity scores for IDDS patients decreased from 6.68 to 2.30 (66% reduction), and for non-IDDS patients from 6.73 to 4.13 (37% reduction; P=0.01). All individual drug toxicities improved with IDDS at both 4 and 12 weeks. At 6 months, only 32% of the group randomized to CMM and who did not cross over to IDDS were alive, compared with 52%-59% for patients in those groups who received IDDS. CONCLUSIONS: IDDS improved clinical success, reduced pain scores, relieved most toxicity of pain control drugs, and was associated with increased survival for the duration of this 6 month trial.

Measurement of IgM responses to a subunit influenza A vaccine by sucrose-gradient centrifugation and membrane-filtration enzyme immunoassays.

IgM responses to a deoxycholate-split influenza vaccine containing the surface antigens of the H3N2 virus A/Philippines/2/82 were studied in five volunteers, three of whom were seronegative by haemagglutination inhibition (HI) tests. Responses were measured by a sucrose-gradient centrifugation technique, in which IgM-specific HI activity was computed as a proportion of total IgM and IgG-specific HI activity, and by a membrane filtration-enzyme immunoassay (MF-EIA). Responses could be detected in all volunteers when measured by sucrose-gradient centrifugation within 1-2 weeks, and the IgM induced was 5-40% of total HI-specific activity. The response was also observed in the presence of low levels of pre-existing antibody. Levels of IgM antibody, when measured by MF-EIA, could be easily detected in two of the volunteers, while those of two others were very low and there was no response in a fifth. No biphasic virus-specific response to vaccination, involving first IgM and then IgG, could be measured by either technique. From these studies, the sucrose-gradient fractionation technique appears to be the more sensitive procedure.

An improved membrane-filtration enzyme immunoassay for the rapid serological diagnosis of viral infections.

A one-step modification of the membrane-filtration enzyme immunoassay (MF EIA) (Barnett et al., J. Clin. Microbiol., 23:385-399, 1987), for estimation of virus-specific antibody is described. The modified MF EIA allowed serum, antigen and enzyme-conjugated anti-globulin to be incubated together in membrane-based 96-well plates to enable the formation of immune complexes in solution at 37 degrees C. The assay required only 45 min for completion and polyethylene glycol was shown to be an essential component in reaction mixtures for IgG assays to enhance immune complex formation. The modified MF EIA was as sensitive as the previous two-step method for monitoring responses to influenza vaccine, and control antigen backgrounds were significantly reduced. The one-step procedure was also shown to be suitable for the rapid serodiagnosis of naturally acquired influenza A and B infections. However, MF EIA detected cross-reactive H1N1 responses in 57.7% of naturally-acquired H3N2 infections, suggesting that responses to common internal antigens were being measured. Cross-reactive responses to influenza A viruses could not be detected in volunteers receiving subunit vaccines.

Freeze-drying of respiratory syncytial viruses for transportation and storage.

The stabilities of eight strains of respiratory syncytial virus were compared after the strains were freeze-dried in the presence and absence of the stabilizer SPGA, which contains 218 mM sucrose, 7.1 mM dipotassium hydrogen phosphate, 3.76 mM potassium dihydrogen phosphate, 4.9 mM sodium glutamate, and 1% (wt/vol) bovine albumin. Strains freeze-dried in the presence of SPGA showed only small-to-negligible losses at 4 degrees C and losses of approximately 2.0 log10 infectious units at 25 degrees C when held for 45 weeks. Losses at 37 degrees C for one strain were approximately 10-fold greater when the strain was freeze-dried in the absence of SPGA. These results indicate that respiratory syncytial virus strains freeze-dried in the presence of a suitable stabilizer can be transported as unrefrigerated samples without undue losses in infectivity.

Age-related responses to influenza vaccination in the Newcastle region during 1983 and 1984.

A study was carried out in Newcastle to assess responses to influenza vaccines in elderly nursing home patients and in younger adults during 1983 and 1984. The decision to vaccinate the elderly subjects was made by their general practitioners. A concurrent randomized placebo-controlled trial of the same vaccine was performed in young adult volunteers. Elderly subjects generally possessed higher levels of pre-existing antibody to the influenzal haemagglutinins that were present in the vaccines than did younger subjects. The highest levels were observed in the 52-63 years' age group. Younger subjects showed significantly greater responses to vaccines compared with elderly subjects (P less than 0.05). Peak responses were noted in the 16-24 years' age group. Of a total of 326 elderly subjects (70% of whom had been vaccinated), six participants, two of whom had been vaccinated, contracted laboratory-proven influenza during 1983. Only one unvaccinated subject of a total of 365 subjects (50% of whom had been vaccinated) contracted influenza during 1984. In both years illness was produced by strain A/Philippines/2/82.

Membrane filtration enzyme immunoassay, a novel, rapid method for measurement of virus-specific immunoglobulins G and M and detection of viral antigens.

A novel membrane filtration enzyme immunoassay (MF EIA) is described in which virus-antibody complexes formed are trapped onto the surface of membranes with low protein-binding affinity by vacuum filtration. Class-specific immunoglobulin G (IgG) or IgM antibody was measured by adding enzyme-conjugated antiimmunoglobulin and incubating prior to the final wash and addition of enzyme substrate. Influenza A virus-specific IgG antibodies measured by MF EIA showed similar sensitivity for detecting seroconversion in volunteers administered influenza virus subunit vaccines and subtype specificity comparable to that observed by the hemagglutination inhibition technique. Cytomegalovirus-specific IgG antibodies measured by MF EIA with commercially available complement fixation antigens gave results similar to those of conventional enzyme-linked immunosorbent assay and complement fixation tests. The MF EIA method is also suitable for detection of rotavirus antigen in feces.

Evaluation of chicken kidney and chicken embryo kidney cultures for the large-scale growth of attenuated influenza virus master strain A/Ann/Arbor/6/60-ca.

Primary chicken kidney (CK) and chicken embryo kidney (CEK) cells were evaluated as possible substrates for growth of the cold-adapted attenuated influenza vaccine master strain A/Ann Arbor/6/60 (A/AA/6/60-ca). Yields of 10(6)-10(7) TCID50 per ml of culture fluid were obtained in either cell type. Yields from the human diploid strain MRC-5 were approximately 100-fold less. More reproducible cultures were obtained from CEK cells, using an overnight trypsinization step at 4 degrees C, than from CK cells. Comparable yields per embryo were obtained from CEK cells grown in roller cultures to those grown on the surface of microcarriers. These yields were less than those obtained from the allantoic fluids of whole embryos. Frozen storage of CEK or CK cells, after primary trypsinization, dispersal from a cultured CK primary monolayer or culture on microcarriers, was unsuccessful. The cold-adapted phenotype of A/AA/6/60-ca was retained after growth in CEK cultures and no differences in immunogenicity were detectable in mice between CEK- and allantoic-grown virus. Allantoic-grown preparations of A/AA/6/60-ca contained a lower protein concentration per infectious unit than those grown in CEK.

Responses to one or two doses of a deoxycholate subunit influenza vaccine in a primed population.

A trial with a trivalent influenza subunit vaccine prepared with sodium deoxycholate was carried out in 88 volunteers between May and November 1981. Each haemagglutinin antigen was present at 7 micrograms per dose. Fourfold or greater haemagglutination inhibition antibody (HI) responses to the H1N1 virus A/Brazil/11/78 occurred in 70% of volunteers following a single dose. For the H3N2 virus A/Bangkok/1/79 and B/Singapore/222/79 these figures were 52 and 11%, respectively. No increase in the antibody titre was noted to any of the antigens following a second vaccination dose. Antibody levels remained relatively constant six months after vaccination. A response to B/Singapore/222/79, comparable with the HI response for the influenza A antigens, was noted when serum titres were estimated by a plaque reduction procedure. No neuraminidase inhibition antibody could be detected in response to either A/Brazil/11/78 or A/Bangkok/1/79. No reactions specifically attributable to the vaccine occurred after either injection. A lower HI response to A/Brazil/11/78 was noted in volunteers 52 years of age and older, who also showed less evidence of earlier priming to this virus. Levels of nasal wash neutralizing antibodies to A/Brazil/11/78 were proportional to those detected in sera by HI tests, but were present in smaller amounts.

The binding of divalent cations to myosin.

Centrifuge transport, equilibrium dialysis, and electron paramagnetic resonance studies on the binding of Mn2+ to myosin revealed two sets of noninteracting binding sites which are characterized at low ionic strength (0.016 M KCl) by affinity constants of 10(6) M-1 (Class I) and 10(3) M-1 (Class II), respectively. At 0.6 M KCl concentration, the affinity of Mn2+ for both sets of sites is reduced. The maximum number of binding sites is 2 for the high affinity and 20 to 25 for the low affinity set. Other divalent metal ions displace Mn2+ from the high affinity sites in the following order of effectiveness: Ca greater than Mg = Zn = Co greater than Sr greater than Ni. The inhibitory effects of Mg2+ and Ca2+ upon the Mn2+ binding are competitive with inhibitor constants of 0.75 to 1 mM which is similar to that of the low affinity divalent metal ion binding sites. Exposure of myosin to 37 degrees partially inhibits Mn2+ binding to Class I parallel with inhibition of ATPase activity. The binding of Mn2+ to the high affinity binding sites is not significantly influenced by ADP or PPi, although Mn2+ increases the affinity of ADP binding to myosin at high ionic strength.