Is the current rate of ~110 patient start forms per month sustainable, or is there an early launch bolus effect?

While there might have been some pent-up urgency, the broad prescriber base, diverse patient demographics (age, severity, incident/prevalent), and remaining opportunities (busy offices, undiagnosed patients, physician experience-building) suggest sustained growth rather than a bolus. “all of the launch metrics that we have been really monitor -- strengthen our belief holistically in terms of this long-term opportunity for sustained ongoing growth in the HO opportunity.”

Given >400 start forms and a previously stated 2,000 identified HO patients, does this imply the identified patient number is now materially larger?

The previously stated 2,000 identified HO patients was from September and has not been updated. The company has been educating additional physicians, and the suspected or diagnosed AHO patient population is continuously growing. “We provided that number back in September, and we have not updated that number. We have been ongoing in terms of since that time, educating additional physicians within our target list, and we still have a ways to go in terms of penetrating the full list. So that number in terms of both that suspected or diagnosed AHO patient population is continuing to grow.”

What is the observed concomitant use of GLP-1s with IMCIVREE in HO patients, and are payers implementing GLP-1 step edits for HO access?

No GLP-1 step-edit requirements are seen in current HO-specific payer policies. Approximately 50% of IMCIVREE-prescribed HO patients had prior or current GLP-1 experience, with 25% still on GLP-1s (for diabetes or obesity). This highlights the unmet need IMCIVREE addresses. “Of the ones that we have in place, there is no step edit requirement in terms of needing to try a GLP before IMCIVREE which is also something that we're pleased overall with.”

RYTM

Rhythm Pharmaceuticals (RYTM) Q2 FY26 earnings call: guidance and Q&A

Earnings call· Jun 2026 (Q2 FY26)· Health Care· Aug 4, 2026

Source: earnings call transcript

Executive summary

Rhythm Pharmaceuticals Q2 FY26 — Strong IMCIVREE HO Launch and Promising RM-718 Data

Rhythm Pharmaceuticals delivered a strong Q2 FY26, driven by the successful U.S. launch of IMCIVREE for acquired hypothalamic obesity, which saw robust patient demand and prescriber engagement. The company also reported encouraging Phase II data for its next-generation weekly MC4R agonist, RM-718, showing comparable efficacy to existing treatments without hyperpigmentation. Despite a one-time international revenue adjustment, the company maintains a solid financial position and is advancing its pipeline and global commercialization efforts.

Highlights

Global net product sales totaled $71.3 million, representing 19% sequential growth over Q1 FY26.
U.S. launch of IMCIVREE for acquired hypothalamic obesity (HO) saw strong demand with over 400 start forms from approximately 300 prescribers in 14 weeks.
RM-718, a weekly MC4R agonist, demonstrated clinically meaningful BMI reductions of 11.6% at week 16 in HO patients, comparable to setmelanotide and bivamelagon, with no generalized hyperpigmentation.
Secured positive payer policies for HO covering approximately 25% of Medicaid and 35% of commercial covered lives by end of Q2 FY26.
Continued growth in patients on reimbursed therapy globally, increasing by over 20% quarter-over-quarter.

Concerns

International revenue decreased from $23.2 million in Q1 FY26 to $20.3 million in Q2 FY26, primarily due to a $3.8 million retrospective charge associated with the French contribution M mechanism.
Two patients discontinued RM-718 Phase II trial due to adverse events (injection site reactions, nausea) within the first 4 weeks of treatment.

Guidance & targets

Category	Target	Timeline	Confidence
Non-GAAP operating expenses	$363 million to $397 million high materiality	FY26	High
Non-GAAP R&D expenses	$175 million to $195 million medium materiality	FY26	High
Non-GAAP SG&A expenses	$188 million to $202 million medium materiality	FY26	High
Cash runway	sufficient to fund planned operations for at least 24 months high materiality	Next 24 months	High
IMCIVREE approval and launch in Japan	by year-end 2026 high materiality	FY26	High
IMCIVREE launch in Germany for acquired HO	in the first half of 2027 medium materiality	H1 2027 · CY27	High
IMCIVREE launches in other European countries for acquired HO	in 2027 following Germany medium materiality	CY27	Medium
Initiate Phase III trial of bivamelagon in RH	over the end of this year high materiality	FY26	High
Enrollment of PWS patients in Part D of RM-718 open-label trial	complete by the end of the year medium materiality	FY26	High

Segment performance

Segment	Revenue	YoY	QoQ	Margin
United States Generated $51 million in product revenue, representing 72% of global product revenue, driven by the strong start of the acquired HO launch and continued growth in BBS. Product revenue % of total: 72%	$51 million	—	—	—
International Revenue decreased to $20.3 million from $23.2 million in Q1 FY26, primarily due to a $3.8 million retrospective charge associated with the French contribution M mechanism, with $2.3 million related to 2025 revenue. Excluding this impact, the international business remains strong with continued patient growth.	$20.3 million	—	—	—

Risks & headwinds

Discontinuation of RM-718 Phase II trial due to adverse events Within first 4 weeks of treatment

2 patients out of 11 enrolled

Mitigation:N/A (acknowledged as part of trial, but overall tolerability profile favorable)

Retrospective charge from French contribution M mechanism impacting international revenue Q2 FY26

$3.8 million ($2.3 million related to 2025 revenue)

Mitigation:N/A (statutory charge)

Busy endocrinology offices and long wait times impacting speed of HO uptake Ongoing

N/A

Mitigation:Teams are persistent in engaging HCPs.

Patients not yet diagnosed with HO Ongoing

N/A

Mitigation:Education of physicians, patient evaluation by HCPs.

Physicians wanting to gain experience with IMCIVREE before prescribing to all patients Early launch phase

N/A

Mitigation:N/A (natural part of new drug adoption).

What to watch in Q3 FY26

IMCIVREE HO launch patient start forms

Next quarter

Current >400 in 14 weeks

Target Sustained growth beyond initial urgency

Why it matters

Indicates the durability and long-term trajectory of the HO market opportunity.

all of the launch metrics that we have been really monitor -- strengthen our belief holistically in terms of this long-term opportunity for sustained ongoing growth in the HO opportunity.

Find out whether RYTM delivers this. Inve re-checks your case every morning.

Q&A highlights

What are the expectations for discontinuation rates for IMCIVREE in HO, and how might they compare to BBS?

It's too early to provide specific HO discontinuation rates. However, the global BBS discontinuation rate was around 30%. HO patients may have lower discontinuation rates due to stronger efficacy seen in clinical studies and potentially easier injection experience. The company is actively monitoring this.

“holistically, there are differences just in terms of what our data has shown in the BBS patient population versus the HO population in terms of the strength of efficacy that may make that discount rate lower in this particular population.”

asked by Tazeen Ahmad · answered by Jennifer Chien

2 min read 6 chapters

Detailed narrative

IMCIVREE U.S. HO Launch Progress

The U.S. launch of IMCIVREE for acquired hypothalamic obesity (HO) has shown strong early demand, with over 400 start forms received from approximately 300 unique prescribers in the first 14 weeks post-FDA approval. Prescriptions are evenly split between patients 21 and younger and those 22 and older, with pediatric patients making up a larger share of early prescriptions.

The majority of prescribers are endocrinologists (43% adult, 37% pediatric), and 65% of priority accounts have been activated.

RM-718 Phase II Data

Preliminary open-label Phase II Part C trial data for RM-718, a weekly MC4R agonist, in acquired HO patients showed a mean BMI reduction of 11.6% at week 16 for 7 patients. These results compare favorably to setmelanotide (10.1% BMI reduction at week 16) and bivamelagon (10.1% BMI reduction at week 14) in similar patient populations.

RM-718 was generally well tolerated, with no observed generalized hyperpigmentation, validating its potential as a viable treatment option.

International Expansion for HO

The European Commission granted marketing authorization for IMCIVREE in acquired HO in May. The company anticipates launching in Germany in H1 2027, with other European countries (France, UK, Italy, Spain, Netherlands) following in 2027. In Japan, IMCIVREE approval for acquired HO and launch are anticipated by year-end 2026, with pricing discussions expected to take 2-3 months post-marketing authorization.

Prader-Willi Syndrome (PWS) Program

Positive 6-month data from the setmelanotide trial in PWS were presented at ENDO, showing clinically meaningful BMI and BMI-Z score reductions, fat mass reduction, lean mass preservation, and improvements in hyperphagia and anxiety. The company expects to update on the path forward for PWS in the next few months, considering setmelanotide, bivamelagon, or RM-718 as viable options.

Enrollment of PWS patients in Part D of the RM-718 open-label trial is expected to complete by year-end.

Payer and GLP-1 Dynamics

Early payer experience for HO has been positive, with positive policies covering approximately 25% of Medicaid and 35% of commercial covered lives by Q2 end, without GLP-1 step-edit requirements. Approximately 50% of IMCIVREE-prescribed HO patients had prior or current GLP-1 experience, with 25% currently on GLP-1s, indicating an unmet need addressed by IMCIVREE.

Commercial Organization Evolution

Rhythm is evolving its North America commercial organization, dedicating 42 territory managers exclusively to HO and establishing a new group of 10 territory managers for BBS. This aims to ensure focused execution for both opportunities and maximize patient reach.

Summary of the company's earnings call; see how call summaries are prepared. Not investment advice.