Radioimmunotherapy of human B-cell lymphoma with 90Y-conjugated antiidiotype monoclonal antibody.

We report the first case of 90Y-conjugated monoclonal antibody (MoAb) administration for human radioimmunotherapy. Ten mCi 90Y-labeled antiidiotype (anti-Id) MoAb were administered to a patient with B-cell lymphoma whose tumor successfully imaged with 111In-labeled anti-Id MoAb. No significant toxicities were observed. More than 2 g of unlabeled anti-Id MoAb were administered while clearing the circulating IgM idiotype prior to administration of the 90Y-MoAb. Transient partial regression of disease was observed. Serial fine needle aspirations of a malignant lymph node documented in vivo anti-Id penetration into a site that did not image by radioimmunoscintigraphy. The radiosensitivity of B-cell lymphoma, the tumor specificity of anti-Id, the antitumor activity of anti-Id alone, and the safe administration of 10 mCi 90Y-labeled anti-Id MoAb in this report suggest further investigation of this radioimmunoconjugate for therapy of B-cell lymphoma is warranted.

Oral 2-chlorodeoxyadenosine in psoriatic arthritis. A preliminary report.

OBJECTIVE: To determine if weekly oral 2-chlorodeoxyadenosine (2-CdA) can induce selective lymphocytopenia, and reduce inflammation, in patients with refractory psoriatic arthritis. METHODS: Seven patients with psoriatic arthritis were treated with oral 2-CdA at weekly dosages of 0.3 mg/kg to 0.45 mg/kg for 12 weeks, followed by monthly maintenance therapy. The patients were evaluated after 6 months. RESULTS: The drug treatment produced selective lymphocytopenia, and reduced lymphocyte infiltration into involved skin. One patient did not complete 12 weeks of therapy because of perceived lack of efficacy. Four of the 6 remaining patients had improved joint disease, and 5 of 6 had improved psoriasis. CONCLUSION: Weekly oral 2-CdA appears to be a well-tolerated regimen for the inducement of peripheral lymphocytopenia in patients with psoriatic arthritis. Larger-scale, controlled trials may be warranted.

Breast cancer imaging with In-111 human IgM monoclonal antibodies: preliminary studies.

Detection of specific tumor sites was studied with scintigraphy and radiolabeled human IgM monoclonal antibodies (MoAbs). Ten patients with metastatic breast cancer received an infusion of one of three indium-111-labeled anti-breast carcinoma MoAbs. The time of infusion ranged from 30 minutes to 2 hours. Three patients received YBB-190 at total doses of 2, 4.25, or 11 mg, four patients received YBM-209 at total doses of 1 mg (n = 1) or 20 mg (n = 3), and three patients each received 22 mg of YBY-088. Imaging was performed immediately after infusion and at 4, 24, 48, 72, 120, and 144 hours. Many presumed sites of metastatic disease were imaged in three of the four patients who received 20 mg of YBM-209 and in two of the three patients who received YBY-088. Tumor was not detected in any of the patients who received YBB-190, in the patient who received a 1-mg dose of YBM-209, or in the patient who received YBY-088 and in whom a biopsy of tumor tissue failed to demonstrate target antigen. The authors conclude that In-111-labeled human IgM MoAbs can target human breast cancer, but antigen expression and antibody dose determine successful immunoscintigraphy.