A Study to Assess the Safety, Tolerability, and Efficacy of IONIS-GHR-LRx Administered in Patients With Acromegaly

Inclusion Criteria: 1. Males or females with a documented diagnosis of Acromegaly\* who are 18 to 75 years old (inclusive) at the time of informed consent. 2. Have had pituitary surgery (e.g. transsphenoidal) unless there was a contraindication to surgery and are either acromegaly medical treatment naïve, or who had not taken any other acromegaly medications prior to the screening visit as outlined below * bromocriptine: 2 weeks * cabergoline: 4 weeks * quinagolide: 4 weeks * octreotide daily injection (SC) or oral formulation: 4 weeks * pegvisomant: 4 weeks * octreotide LAR: 3 months * pasireotide LAR: 4 months * lanreotide (all formulations): 3 months 3. At Screening, serum IGF-1 (performed at the central lab) between 1.3 to 5 × ULN, inclusive, adjusted for age and sex. 4. Females must be non-pregnant and non-lactating, and either surgically sterile, post-menopausal, abstinent, or using 1 highly effective method of birth control Exclusion Criteria: 1. Participants who received surgery for pituitary adenoma within the last 3 months before the trial, and/or planning to receive surgery during the trial 2. Participants who received radiotherapy for pituitary adenoma within the last 2 years before the trial, and/or planning to receive radiotherapy during the trial 3. Participants with a pituitary tumor that, per Investigator judgment, is worsening (e.g., either growing or at risk of compressing or abutting the optic chiasm or other vital structures) as assessed by pituitary/sellar MRI protocol at Screening or within 3 months of Screening. CT scan is allowed if MRI is contraindicated 4. Evidence of decompensated cardiac function per medical judgement and/or New York Heart Association (NYHA) Class 3 or 4 5. Clinical evidence of symptomatic hyperprolactinemia that would necessitate treatment 6. Symptomatic cholelithiasis, and/or choledocholithiasis