A controlled study of the effectiveness of the Rinkel method of immunotherapy for ragweed pollen hay fever

In a double-blind study, we compared the effects of the Rinkel method of immunotherapy with ragweed pollen extract and placebo on symptoms of ragweed hay fever and immunologic parameters in 24 ragweed-sensitive patients. Each had a skin-test end point by Rinkel serial dilution titration to ragweed pollen extract at 1:312,500 w/v or greater dilution, a 2+ skin test to ragweed AgE at 0.1 μg/ml or greater dilution, and in vitro leukocyte histamine release by ragweed pollen extract. None had had immunotherapy for at least 7 yr. Patients matched on the basis of leukocyte histamine release by ragweed were assigned to two treatment groups (12 patients in each group). One group received ragweed pollen extract, and the other, placebo, both administered by the Rinkel method between June and October, 1978. Treatment doses were derived from skin-test end points. The median maintenance (“optimal dose”) for patients receiving ragweed pollen extract was 0.53 ml of 1:312,500 w/v and the mean cumulative dose of ragweed pollen extract given during the study contained 0.094 μg of ragweed AgE. Symptom-medication scores of all patients rose and fell with ragweed pollen counts. No significant differences were observed in mean daily symptom-medication scores, antiragweed IgG or IgE levels, leukocyte histamine release by ragweed, total IgE levels, or skin-test end-point dilutions with ragweed pollen extract between the group receiving ragweed pollen extract and the group receiving placebo. Despite the absence of specific effect on symptom-medication scores and measured immunologic variates, 10 of the 12 ragweed-treated patients and 10 of the 12 placebo-treated patients were of the opinion that their hay fever symptoms during the ragweed pollen season were less severe in 1978 than in 1977 and that they had been helped by Rinkel method immunotherapy. Under the conditions of the study, Rinkel method immunotherapy with ragweed pollen extract was no more effective than placebo given in an imitation of the Rinkel method.     

A comparison of immunotherapy schedules for injection treatment of ragweed pollen hay fever

In 44 patients highly sensitive to ragweed, we compared weekly injections of single doses of ragweed extract (RW-Wk, 15 patients) with clustered doses of ragweed extract at 3-wk intervals (RW-Cl, 18 patients) and with placebo (11 patients) for effects on ragweed hay fever symptom-medication scores and immunologic variates. Patients were matched and randomly assigned to treatment groups. Ragweed doses were advanced to the highest tolerated dose. Doses and number of visits were lower in the RW-Cl group than in the RW-Wk group. Despite lower doses, systemic reactions were not reduced and antiragweed IgE levels increased significantly more in the RW-Cl group than those in the RW-Wk group. Both the RW-Cl and RW-Wk groups had significant increases in antiragweed IgG levels, decreases in seasonal rise in antiragweed IgE levels, and lower symptom-medication scores (p < 0.01) in comparison with the placebo group. We conclude that the RW-Cl regimen offered no important advantage over RW-Wk. Seventeen patients had previously received Rinkel-method immunotherapy with 0.5 ml of end-point dilution of ragweed extract for 1 to 2 yr without significant clinical improvement or immunologic changes. After adequate treatment with either RW-Wk or RW-Cl, these patients had significantly lower symptom-medication scores than those of the placebo group and immunologic changes similar to those of the entire active-treatment group. Therefore, treatment failures on Rinkel immunotherapy respond well to adequate dose immunotherapy by either schedule.     

Comparison of Rinkel injection therapy with standard immunotherapy

We compared the results of a controlled, double blind study of standard immunotherapy (SIT) in subjects with ragweed hay fever during 1980 with the results of our study of Rinkel injection therapy (RIT) in a group of subjects with ragweed hay fever in 1979. Both groups were of comparable sensitivity. During the 1980 hay fever season in Milwaukee, 20 subjects with atopic rhinitis due to ragweed pollen (eight from the 1979 group treated with RIT) were given SIT (Tr), while 14 matched subjects (eight from the 1979 placebo group) were treated with a histamine placebo (Pl). The same glycerinated aqueous ragweed extract and glycerinated histamine placebo were used in both studies. The mean cumulative dose of ragweed extract in the 1980 study was 5391 PNU (20.1 μg of antigen E [AgE]) as compared with 41.5 PNU (0.16 μg of AgE) in 1979. Results indicated a significantly lower weekly mean symptom score (SxSc) in the Tr group compared with that of the Pl group in 5 of the 6 wk that ragweed pollen was counted in 1980. Weekly mean medication score (MxSc) and physical exanination score (PESc) showed similar but less striking differences. The mean seasonal SxScs, MxScs, and PEScs of the SIT Tr group were significantly lower than those of the Pl group in 1980 as well as those of the RIT Tr group in 1979. The same indices were also significantly lower in 1980 by paired analyses in the subset of eight subjects treated in both years. RAST scores showed a significant decrease in the “after season” means in the Tr group as compared with the Pl group in 1980 but not in 1979 (analysis of covariance). We conclude that SIT is more effective than a placebo or RIT in reducing SxSc, MxSc, and PESc as well as in diminishing postseason RAST values. We cannot recommend therapy as proposed by Dr. H. J. Rinkel for clinical use at this time.     

Polymerized whole ragweed: A two-year follow-up of patients treated with an improved method of immunotherapy

We have previously reported, in a 1-yr study, the effectiveness of polymerized ragweed (PRW) as an improved method of immunotherapy for patients suffering from ragweed hay fever. In that study, treatment with PRW was found to be superior to treatment with monomer ragweed extract (MRW) because of the reduced allergenicity of the PRW. The current study is a 2-yr follow-up of nine patients treated with PRW and nine patients treated with MRW. After 1 yr of immunotherapy, both MRW- and PRW-treated patients received 9,000 protein nitrogen units (PNU) and after a second year of maintenance therapy both groups received a cumulative dose of 15,000 PNU. Serum blocking antibody against ragweed antigen E (AgE) was measured periodically during the study. After 1 yr of immunotherapy, blocking antibody in the PRW- and MRW-treated groups was similar with respective means of 1,300 and 1,500 ng AgE bound per milliliter of serum. At the end of 2 yr of therapy, these serum AgE binding activities rose to 2,700 and 4,100, respectively. No significant local or systemic reactions occurred in the PRW-treated group during the year of maintenance therapy. However, large local reactions prevented three of the nine patients treated with MRW from achieving a monthly maintenance schedule. A significant decrease in rhinitis symptoms was noted in both treated groups as compared with the season before immunotherapy and also to a group of patients untreated with immunotherapy during the 1978 ragweed season.     

A multi-institutional trial of polymerized whole ragweed for immunotherapy of ragweed allergy

Eighty ragweed-sensitive patients in four cities were recruited to study the safety and efficacy of partially purified, polymerized whole ragweed (PRW) as an improved form of immunotherapy. Groups of 20 patients in Chicago, Boston, Memphis, and St. Louis had blood drawn for immunologic studies before and after the 1978 and 1979 ragweed seasons and completed detailed daily symptom score sheets each day of the 1978 and 1979 ragweed pollen seasons. Beginning in March, 1979, all patients except one received 15 weekly injections of PRW totaling 50,000 protein nitrogen units (PNU) and containing about 500 μg ragweed AgE. One patient received 25,000 PNU. Symptom score indices of the posttreatment 1979 season were compared with those from the pretreatment 1978 season and also with the scores of similar groups of ragweed-sensitive patients in each city treated only with medication for symptomatic relief during the 1979 season. Local reactions to polymerized ragweed immunotherapy were minimal. No abnormalities in complete blood count, erythrocyte sedimentation rate, chest x-ray film, urinalysis, or rheumatoid factor occurred in the immunotherapy-treated groups. Total serum antibody binding of ragweed AgE increased 12-fold following immunotherapy. When compared either with their 1978 untreated group scores or when compared with scores from the untreated group in each city in 1979 (control group), the symptom score indices of the immunotherapy-treated groups in 1979 were significantly improved. PRW is efficacious in the treatment of ragweed hay fever and can be administered more safely and in higher doses with fewer injections than conventional extracts. It represents an improved form of immunotherapy.     

Effect of immunotherapy on immunoglobulin E and immunoglobulin G antibodies to ragweed antigens: a six-year prospective study

The effect of immunotherapy with aqueous short ragweed (SRW) extract on IgE and IgG antibodies was tested over a 6 yr period in 47 adults with ragweed hay fever. Sera were collected each year in July and October from 1973 through 1979. In May 1976, 23 patients began immunotherapy with a lyophilized standardized SRW extract. From 1976 through 1979, treated patients received an average total dose of 4.8 × 10³ protein nitrogen units (1039 μg of AgE). IgE antibodies to SRW and ragweed AgE were measured by the radioallergosorbent test (RAST) in antigen excess using allergens bound to Sepharose. Blocking antibodies primarily of the IgG class were measured by RAST interference. In response to inhalation of ragweed pollen, untreated patients showed seasonal rises (July to October) and postseasonal falls (October to July) of IgE antibodies during the entire study period. IgE antibody levels in the untreated patients decreased with time and from 1974 to 1979 fell 41% (p < 0.003) for an average halftime of 6.2 yr. Before immunotherapy, treated patients also showed seasonal rises and postseasonal falls. Treatment with SRW extract in 1976 produced an abrupt increase in IgE and IgG antibodies and a clear-cut suppression of seasonal rises of IgE antibodies without an effect on postseasonal falls through 1978. From 1974 to 1979, IgE antibodies to AgE and SRW decreased more in the immunized group than in the control group, and by 1979 these levels showed a mean fall of 73%. Blocking antibodies increased in the treated patients and reached maximal levels by July 1978. In 1978 and 1979, the levels of IgG blocking antibodies to AgE were inversely related to the IgE antibody levels to AgE. These results indicate that adults with ragweed hay fever show regular seasonal and postseasonal changes in IgE antibodies and that IgE antibodies spontaneously decrease with time. Immunotherapy magnifies these decreases by suppression of the seasonal rises, but it does not affect the postseasonal falls.     

The role of ragweed pollen in autumnal asthma

Thirty-nine ragweed-allergic seasonal asthmatics were studied from 1972 to 1974. After quantitative skin tests, antigen E-induced leukocyte histamine release, quantitative inhalation bronchial challenge with ragweed extract to determine PD35 (provocation dose of allergen causing 35% decrease in specific airways conductance), and radioallergosorbent test (RAST) determinations were done, patients were paired based on PD35 values and randomly assigned to treatment or placebo groups, receiving either aqueous ragweed extract or placebo prior to the 1973 ragweed season. Treated patients received a mean cumulative dose of extract equivalent to 11.7 microng antigen E (4,180 protein nitrogen units [PNU]). Twenty-nine patients were followed through the ragweed season with daily symptom diaries and biweekly physician examinations. Severity of disease was not predictable by PD35 data, skin tests, leukocyte histamine release, or radioallergosorbent test (RAST) values. Although all patients were ragweed-allergic by objective tests, only 13/29 had asthma symptoms correlating with ragweed counts. Mold spore counts were related significantly to symptoms in some patients. Asthma and hay fever symptoms correlated significantly in 24/29 patients. This dose of immunotherapy caused no significant difference to be found in asthma or hay fever symptoms in treated versus placebo patients for the 1973 reporting period as determined by physician evaluations or daily symptom diaries. No patients showed significant improvement in PD35 values after treatment in 1973. Similar findings were obtained for a smaller group of patients followed through the 1974 ragweed season who received a mean dose of 31.2 microng antigen E (11,140 PNU). The failure of these patients to show a response to immunotherapy could be due to a combination of the relatively low dose of ragweed extract and their sensitivity to other allergens.     

Reactivity of ragweed allergens with IgE antibodies. Analyses by leukocyte histamine release and the radioallergosorbent test and determination of cross-reactivity.

Five distinct proteins with allergenic activity have been isolated from short ragweed pollen. We initially tested three of these, AgE, AgK, and Ra3, for reactivity with IgE antibodies by leukocyte histamine release and by the radioallergosorbent test (RAST). We found highly significant correlations between the reactivities of these allergens by leukocyte histamine release and by the RAST, consistent with the view that both procedures detected comparable allergenic activity. We next tested the allergenic cross-reactivity of all five ragweed allergens. AgE, AgK, Ra3, Ra4, and Ra5, by RAST inhibition. With solid-phase AgE the only nonhomologous inhibitor was AgK, which cross-reacted weakly and required a 140-fold mass excess of AgK compared to AgE. With solid-phase AgK both AgK and AgE produced significant inhibition; AgE was slightly more potent than the homologous AgK, Ra3 and Ra5 were allergenically unique, because only the homologous allergen produced 50% inhibition. Ra4 was weakly inhibited by AgE, Ra3, and Ra5 when these allergens were added in 300- to 5---fold mass excesses; this weak inhibition may represent either cross-reaction or cross-contamination. We found that RAST inhibition could be used as an assay for the individual ragweed allergens and we demonstrated the presence of all of the allergens in a whole ragweed extract. The sensitivity of the RAST inhibition assay ranged from 10 ng to 100 ng for 50% inhibition. Finally, the solid-phase ragweed allergens were used to determine the frequency of elevated IgE antibody levels in 65 patients with ragweed hay fever. Virtually all of the patients reacted with AgE (97%), while 88% reacted with AgK, 51% reacted with Ra3, 28% reacted with Ra4, and 17% reacted with Ra5. These results highlight the usefulness of the RAST as a specific and sensitive tool for immunochemical studies of allergens.     

Index to volume 66

Eighty ragweed-sensitive patients in four cities were recruited to study the safety and efficacy of partially purified, polymerized whole ragweed (PRW) as an improved form of immunotherapy. Groups of 20 patients in Chicago, Boston, Memphis, and St. Louis had blood drawn for immunologic studies before and after the 1978 and 1979 ragweed seasons and completed detailed daily symptom score sheets each day of the 1978 and 1979 ragweed pollen seasons. Beginning in March, 1979, all patients except one received 15 weekly injections of PRW totaling 50,000 protein nitrogen units (PNU) and containing about 500 μg ragweed AgE. One patient received 25,000 PNU. Symptom score indices of the posttreatment 1979 season were compared with those from the pretreatment 1978 season and also with the scores of similar groups of ragweed-sensitive patients in each city treated only with medication for symptomatic relief during the 1979 season. Local reactions to polymerized ragweed immunotherapy were minimal. No abnormalities in complete blood count, erythrocyte sedimentation rate, chest x-ray film, urinalysis, or rheumatoid factor occurred in the immunotherapy-treated groups. Total serum antibody binding of ragweed AgE increased 12-fold following immunotherapy. When compared either with their 1978 untreated group scores or when compared with scores from the untreated group in each city in 1979 (control group), the symptom score indices of the immunotherapy-treated groups in 1979 were significantly improved. PRW is efficacious in the treatment of ragweed hay fever and can be administered more safely and in higher doses with fewer injections than conventional extracts. It represents an improved form of immunotherapy.     

Comparison of immune reactivity to polyvalent monomeric and polymeric ragweed antigens

The proteins of an aqueous extract of ragweed pollen (RW) were precipitated at 90% saturation with (NH4)2SO4, solubilized, and sieved through Sephadex G-15. The excluded fraction, termed the monomeric form (MRW), was cross-linked with glutaraldehyde to form polymerized ragweed (PRW). As compared with MRW, PRW is more immunogenic in rabbits in the production of antibody against RW antigen E (AgE). MRW and PRW resulted in equal peak reaginic responses in rabbits but the duration of reagin production was longer after immunization with MRW than with PRW. Both MRW and PRW have exposed antigenic determinants of AgE but PRW had approximately 1/3 the number as shown by neutralization of human antibody against RW AgE. PRW had 100-to 1,000-fold less human cutaneous reactivity than MRW. PRW may be a more easily effective therapeutic agent for human RW immunotherapy than currently used aqueous extracts and may be more readily obtainable than polymerized AgE.     

Measurement of the absolute levels of IgE antibodies in patients with ragweed hay fever: Effect of immunotherapy on seasonal changes and relationship to IgG antibodies

The effect of immunotherapy with aqueous ragweed pollen extract on changes in IgE antibody was analyzed in 40 untreated patients with ragweed hay fever and compared to changes in 63 treated patients. Treated patients received cumulative doses prior to and during treatment ranging from 1.4 × 10⁵ to 4.8 × 10⁶ protein nitrogen units (PNU). IgG antibody to ragweed antigen E (AgE) was measured by radioimmunoprecipitation, while IgE antibody to allergens in crude ragweed extract was measured by the radioallergosorbent test (RAST). The RAST procedure was calibrated using a serum whose content of IgE antibody in nanograms per milliliter had been determined by immunoabsorption, and with this method the absolute quantities of IgE antibodies to ragweed allergens could be measured. Control experiments indicated that the IgG antibodies in the sera of the treated patients did not interfere with the measurements of IgE antibodies. The levels of IgE antibody in serum varied from less than 5 ng/ml to approximately 3,000 ng/ml. IgE antibodies decreased from October, 1973, to July, 1974, and rose sharply from July to October, 1974, following the pollination season. In both untreated and treated patient groups the magnitudes of the decreases were related (p < 0.001) to the levels of IgE antibody in October, and the magnitudes of the rises were related to the levels of IgE antibody in July. In the treated patients with IgE antibody less than 71 ng/ml in October, the rate of decrease (October to July) was less than in the untreated patients. Comparison of the rises in IgE antibody from July to October revealed that these were partially suppressed in the treated group (p < 0.001), and this effect was most marked in patients with July levels less than 36 ng/ml. Levels of IgG antibody to AgE in the treated patients were approximately 70-fold greater than in untreated patients and showed little change over the study period. The levels of IgG and IgE antibody in the treated patients were positively correlated (p < 0.001) at all time periods, and patients with high levels of IgG antibody also had greater declines and rises in IgE antibodies. The results indicate that immunotherapy is associated with (1) a reduction in the seasonal decrease in IgE antibody from October to July in patients with the low levels of IgE antibody, (2) a partial suppression of the rises in IgE antibody from July to October, and (3) that both these effects are related to the level of IgE antibody before the change. In many treated patients both IgE and IgG antibodies were low in spite of parenteral administration of ragweed extract. This result is consistent with the view that overall humoral immunologic reactivity to ragweed antigens is reduced in these patients.     

The clinical and immunologic specificity of immunotherapy

In order to study the specificity of immunotherapy for respiratory allergy, a group of patients sensitive to both ragweed and grass pollens were selected. From 87 volunteers with a history of both spring and fall hay fever, 42 patients with evidence of strong sensitivity by basophil histamine release to both ragweed pollen and mixed grass pollen extracts were selected for study. On the basis of the histamine release data, the patients were divided into two groups matched for sensitivity to both grass and ragweed pollens. In 1970, May and June symptom diaries showed the two groups to suffer quite similar severity of symptoms during the grass pollination season. One group of patients was started on a preseasonal course of immunotherapy with alum-precipitated aqueous extract of ragweed pollen while the other group received placebos containing histamine. By fall there had been a considerable rise in IgG-blocking antibodies to ragweed in the treated group. Symptom diaries in August and September showed that the treated group showed significantly less severe symptoms than the placebo group. Both groups received booster injections at 2-wk intervals from the fall of 1970 to the fall of 1971. Doses in the treated group were raised to attempt to administer the largest possible dose. Again there was no difference in the symptoms reported by the two groups during the grass pollination season, but an even greater difference emerged between the two groups during the ragweed season. The following year 1972 the same results were obtained. These data demonstrate that treatment with ragweed pollen extracts has little or no effect on grass pollen symptoms and confirm that immunotherapy is clinically as well as immunologically specific. Antibody responses to the second year of high-dosage booster injections was not greater than responses to a comparatively short preseasonal course given the first year.     

Polymerized whole ragweed: Human safety and immune response

Polymerized ragweed (PRW) has been shown to have reduced allergenicity while maintaining immunogenicity. In order to evaluate whether the reduced allergenicity would permit high initial doses and rapid progression to maintenance, two groups of subjects with ragweed pollenosis were placed on immunotherapy with PRW standardized for antigen E (AgE) content. Group I, 28 subjects, received an initial dose of 100 protein nitrogen units (PNU) (1 μg AgE) and reached a maintenance dose of 1,000 PNU (10 μg AgE) in four weekly injections. In the first 10 wk each subject received 7,850 PNU (78.5 μg AgE). Group II, six subjects, received an initial dose of 100 PNU (1 μg AgE) and after 11 weekly injections received 30,000 PNU (300 μg AgE). No anaphylactic reactions occurred in the study groups. In group I, three large immediate-type local reactions and nine large late-type reactions occurred in 110 injections. Anti-AgE antibody activity in group I rose from a pretreatment mean value of 264 ng AgE bound per milliliter serum to a posttreatment value of 3,182. The major rise occurred after only 4 wk of therapy. In group II, anti-AgE antibody activity rose from 66 to 2,123 after the 11 wk of therapy. IgE antibody to AgE did not change to any extent in either group, and histamine release in response to AgE measured in group II patients did not change. Symptom score evaluation of group I patients revealed a marked decrease in symptoms after therapy with PRW. Immunotherapy with PRW can be initiated at higher doses, with rapid attainment of maintenance dosage with safety resulting in a brisk immune response and symptomatic improvement.     

Local nasal immunotherapy: efficacy of low-dose aqueous ragweed extract

In previous studies preseasonal local nasal immunotherapy (LNIT) with moderate doses of aqueous ragweed extract (mean total dose 59 micrograms of AgE and 139 micrograms of AgE) was an effective treatment for ragweed hay fever; however, local adverse reactions during therapy were common. This study evaluated the clinical and immunologic responses to LNIT by use of lower doses of aqueous ragweed extract in order to minimize these adverse reactions. Patients were administered preseasonal LNIT for 7 wk and received a mean total dose of 4.7 micrograms of AgE. During the ragweed season, symptom/medication scores (SMS) of the treated patients were equivalent to SMS of untreated patients. Serum ragweed-specific IgE and nasal secretory ragweed-specific IgA rose slightly in the treated patients but not to the extent observed in previous studies. After the ragweed season treated and untreated patients had a substantial increase in serum ragweed IgE antibody titers. No correlation could be found between antibody responses and SMS. This study indicates that LNIT with lower doses of aqueous ragweed extract is clinically ineffective.     

Polymerized whole ragweed: An improved method of immunotherapy

A single-blind study compared the effectiveness of glutaraldehyde-treated polymerized ragweed with nonpolymerized monomeric ragweed. These studies are an extension of those previously reported for polymerized AgE using a readily available ragweed preparation containing all ragweed antigens. Nineteen ragweed-sensitive patients were randomized into 2 groups; 10 received the polymerized form and 9 received the monomeric form. Four parameters were followed: serum-specific IgE against antigen E, total blocking antibody against antigen E, local and systemic reactions to injection therapy, and symptom score indices. Pretreatment levels of antigen E-specific IgE and blocking antibody activity were similar in both groups. After a total of 15,000 protein nitrogen units (PNU) had been given, blocking antibody activity in the monomer group rose from a mean of 173 ng AgE bound per ml to a mean of 2,813. The rise in blocking antibody activity in the polymer group was from a mean of 181 ng AgE bound per ml to 1,574. At 15,000 PNU, blocking antibody activity levels were not statistically different in the 2 groups. After 1 year of treatment, no consistent decrease in postseasonal specific IgE rise could be shown in either group. Forty times less erythema and 15 times less induration were found with polymerized ragweed. There were 7 systemic reactions with the monomer and none with the polymer. Both groups experienced symptomatic improvement with treatment.     

Standardization of antigen E in ragweed pollen extracts using a monoclonal antibody-based enzyme immunoassay

A hybridoma-derived monoclonal IgG antibody specific for ragweed AgE was used to develop a competitive binding enzyme immunoassay suitable for quantitation of antigen E levels in ragweed pollen extracts. The assay was capable of detecting as little as 30 ng/ml AgE in crude pollen extracts. The monoclonal antibody was shown to react with AgE present in commercial pooled pollen extracts from a number of ragweed species as well as a laboratory extract from a single species. In contrast to previous conventional xenoantisera, it could distinguish true ragweed (Ambrosia sp) from false ragweed (Franseria sp). The use of monoclonal antibodies in assay systems such as this offers a reproducible and widely applicable method for allergen standardization.     

Diagnostic tests in ragweed hay fever. A comparison of direct skin tests, IgE antibody measurements, and basophil histamine release

In 87 patients with both spring and fall hay fever symptoms the radioallergosorbent test (RAST) technique for specific IgE antibodies to ragweed was compared with basophil histamine release and direct intradermal skin testing by the threshold dilution technique. The three techniques gave good agreement except with the leastsensitive patients, some of whom had a positive skin test but undetectable histamine release or IgE antibodies. Twenty-one patients who were highly sensitive to ragweed as measured by all three techniques were followed without specific immunotherapy. There was significant agreement between the level of positivity of all three tests and the symptom index obtained during the ragweed season. In 14 of the 21 patients there was a significant correlation between daily ragweed pollen counts and daily symptom indexes during the season. On the other hand, among the 16 least-sensitive patients (as judged by histamine release) the correlation between daily ragweed pollen counts and symptom indexes was significant in only 3 patients. Other significant allergens could not be identified in the latter group, and the cause of their symptoms is not clearly identified but appears not to be ragweed. The RAST is a quantitative technique that gives diagnostically useful information in ragweed hay fever, although not significantly different from basophil histamine release or carefully performed skin testing. The convenience to the patient may, however, offer a noticeable advantage.     

A double-blind, placebo-controlled trial of polymerized whole ragweed for immunotherapy of ragweed allergy

Immunotherapy with polymerized ragweed (PRW) has been demonstrated to be safe and effective when compared with monomeric ragweed or untreated controls. To further establish the efficacy of PRW, a trial was conducted comparing PRW, placebo, and no treatment in ragweed-sensitive individuals. In a double-blind manner, 21 patients were treated before the 1981 ragweed season with 15 weekly injections of PRW totaling about 50,000 PNU and 1200 μg antigen E, while 19 patients were treated with 15 weekly injections of a caramelized glucose and histamine placebo. An additional control group received no injections. Blood was drawn for IgE against ragweed antigen E (IgE-a-AgE) and for blocking antibody against AgE before treatment, after treatment (before season), and after season. In the untreated patients, blood was drawn before season and after season. Daily symptom score sheets were completed by patients each day of the ragweed season. Blocking antibody rose more than 40-fold with treatment (p = 0.0001) in the PRW group but was unchanged in the placebo group with treatment. IgE-a-AgE rose with PRW therapy. Clinical efficacy of PRW was again confirmed in this study. Symptom score mean in the PRW group was statistically lower than the mean in the placebo group (p = 0.022) and in the untreated group (p = 0.018). There were no systemic reactions and only minor local reactions during treatment. In summary, PRW is an improved form of immunotherapy.     

Rinkel injection therapy: a multicenter controlled study

The American Academy of Allergy sponsored a 2-yr “double blind” multicenter study of the effect of Rinkel injection therapy (RIT) compared with a histamine placebo in subjects with atopic rhinitis. Accumulated data included the symptom, medication, and physical examination scores and specific IgE antibody levels measured by the radioallergosorbent test (RAST). A total of 155 subjects (81 treated, 74 placebo) entered the project from six centers during their respective ragweed, grass, and mountain cedar pollen (from one center) seasons for a total of 11 pollen seasons. The total mean cumulative dose of extract was 18.6 PNU, which is much lower than recommended for standard immunotherapy. With one exception, none of the centers reported a consistent significant difference between the pollen extract-treated and placebo-treated groups in any of the weekly mean scores or the RAST before, during, and after the pollen seasons. For 4 wk after the height of the mountain cedar season the group treated with pollen extract showed a significant decrease in weekly mean symptom and medication scores as compared with the placebo group. The overall comparison of the mean seasonal scores for the entire study, however, showed no significant difference between the treated and placebo groups. We conclude the RIT is no more effective than a histamine placebo in influencing the weekly mean symptom, medication, and physical examination scores or IgE antibody levels.     

Cromolyn sodium nasal solution in the prophylactic treatment of pollen-induced seasonal allergic rhinitis.

A large-scale multicenter investigation was undertaken in 3 cities with comparable pollen seasons and atmospheric pollen concentrations in order to obtain more definite information about the safety and efficacy of cromolyn sodium in the treatment of pollen-induced seasonal rhinitis. The 9-wk double-blind study was conducted in 104 patiets in Pittsburgh, Pa., Cleveland, Ohio, and Louisville, Ky., during the 1975 ragweed season. It indicated that a nebulized 4% aqueous solution of cromolyn sodium is effective in reducing sneezing, rhinorrhea, nasal congestion, and ocular irritation in ragweed hay fever patients. The efficacy of the drug was notable despite the fact that patients used an average of 52 mg instead of the recommended 62.4 mg daily. Cromolyn sodium did not appear to have a significant effect on transseasonal antiragweed IgE (IgEAR) levels. Patients acceptance of the cromolyn nasal solution was good, and there were no significant adverse reactions. The side effects, which were distributed equally between the drug and placebo groups, were mild and of limited duration.