The clinical trials of octreotide acetate for injectable suspension were performed in patients who had been receiving octreotide acetate injection for a period of weeks to as long as 10 years. The acromegaly studies with octreotide acetate for injectable suspension described below were performed in patients who achieved GH levels of < 10 ng/mL (and, in most cases < 5 ng/mL) while on subcutaneous octreotide acetate injection. However, some patients enrolled were partial responders to subcutaneous octreotide acetate injection, i.e., GH levels were reduced by > 50% on subcutaneous octreotide acetate injection compared to the untreated state, although not suppressed to < 5 ng/mL. 

Octreotide acetate for injectable suspension was evaluated in three clinical trials in acromegalic patients.

In 2 of the clinical trials, a total of 101 patients were entered who had, in most cases, achieved a GH level < 5 ng/mL on octreotide acetate injection given in doses of 100 mcg or 200 mcg three times daily. Most patients were switched to 20 mg or 30 mg doses of octreotide acetate for injectable suspension given once every 4 weeks for up to 27 to 28 injections. A few patients received doses of 10 mg and a few required doses of 40 mg. Growth hormone and IGF-1 levels were at least as well controlled with octreotide acetate for injectable suspension as they had been on octreotide acetate injection and this level of control remained for the entire duration of the trials.

A third trial was a 12-month study that enrolled 151 patients who had a GH level < 10 ng/mL after treatment with octreotide acetate injection (most had levels < 5 ng/mL). The starting dose of octreotide acetate for injectable suspension was 20 mg every 4 weeks for 3 doses. Thereafter, patients received 10 mg, 20 mg, or 30 mg every 4 weeks, depending upon the degree of GH suppression [see Dosage and Administration (2)]. Growth hormone and IGF-1 were at least as well controlled on octreotide acetate for injectable suspension as they had been on octreotide acetate injection.

Table 5 summarizes the data on hormonal control (GH and IGF-1) for those patients in the first two clinical trials who received all 27 to 28 injections of octreotide acetate for injectable suspension.

For the 88 patients in Table 5, a mean GH level of < 2.5 ng/mL was observed in 47% receiving octreotide acetate for injectable suspension. Over the course of the trials, 42% of patients maintained mean growth hormone levels of < 2.5 ng/mL and mean normal IGF-1 levels.

Table 6 summarizes the data on hormonal control (GH and IGF-1) for those patients in the third clinical trial who received all 12 injections of octreotide acetate for injectable suspension.

For the 122 patients in Table 6, who received all 12 injections in the third trial, a mean GH level of < 2.5 ng/mL was observed in 66% receiving octreotide acetate for injectable suspension. Over the course of the trial, 57% of patients maintained mean growth hormone levels of < 2.5 ng/mL and mean normal IGF-1 levels. In comparing the hormonal response in these trials, note that a higher percentage of patients in the third trial suppressed their mean GH to < 5 ng/mL on subcutaneous octreotide acetate injection, 95%, compared to 78% across the 2 previous trials.

In all 3 trials, GH, IGF-1, and clinical symptoms were similarly controlled on octreotide acetate for injectable suspension as they had been on octreotide acetate injection.

Of the 25 patients who completed the trials and were partial responders to octreotide acetate injection (GH > 5.0 ng/mL but reduced by > 50% relative to untreated levels), 1 patient (4%) responded to octreotide acetate for injectable suspension with a reduction of GH to < 2.5 ng/mL and 8 patients (32%) responded with a reduction of GH to < 5.0 ng/mL.

Two open-label clinical studies investigated a 48-week treatment with octreotide acetate for injectable suspension in 143 untreated (de novo) acromegalic patients. The median reduction in tumor volume was 20.6% in Study 1 (49 patients) at 24 weeks and 24.5% in Study 2 (94 patients) at 24 weeks and 36.2% at 48 weeks.